The Journal of Thoracic and Cardiovascular Surgery, 1995
The use of endovascular devices as an adjunct to repair of congenital heart anomalies represents ... more The use of endovascular devices as an adjunct to repair of congenital heart anomalies represents a novel but unproven therapeutic approach. Intraoperative implantation of pulmonary arterial stents (5 to 15 mm diameter) was done in 11 patients with pulmonary atresia with ventricular septal defect (n = 4), classic tetralogy of Fallot (n = 2), truncus arteriosus (n = 1), hypoplastic left heart syndrome (stage II [n = 1] and stage III In = 1] Norwood procedure), and miscellaneous pulmonary arterial stenoses (n = 3), as well as in patients with congenital (n = 1) and postoperative (n = 3) pulmonary venous osbstruction and in 1 patient with combined pulmonary arteria~ and venous obstruction. The stents were effective at achieving immediate patency in all patients. There were two early deaths, one related to acute thrombosis of a small-diameter left pulmonary artery stent. Reintervention because of stentrelated pulmonary arterial stenosis was frequently necessary. In five of seven patients who survived more than I month after implantation of stent size 8 mm or smaller severe stent-related pulmonary arterial obstruction developed. In four of the five patients with pulmonary vein stent implantation intractable obstruction developed, resulting in death in all three patients who had bilateral pulmonary vein stent implantation. Intraoperative occlusion of apical muscular ventricular septal defect with use of a clamshell device inserted from the right atrial approach was accomplished in four patients. One patient who underwent associated aortic arch reconstruction died as a result of left ventricular hypoplasia. The results in the remaining three patients were favorable on the basis of absence of significant late residual intraventricular shunting, left ventricular dysfunction, or arrhythmia. We conclude that recurrent intraluminal obstruction as a result of neointimal hyperplasia appears to be an eventual certainty in currently designed small-diameter endovascular stents. For this reason, we would recommend standard surgical techniques for repair of obstructive lesions of the pulmonary arterial confluence to maximize growth potential. Device occlusion of muscular ventricular septal defects is feasible but probably only indicated for complex cases of ventricular septal deficiency that otherwise necessitate a left ventriculotomy.
A randomized trial of arterial duct occlusion with a double umbrella (DU) or wire coil (WC) was u... more A randomized trial of arterial duct occlusion with a double umbrella (DU) or wire coil (WC) was undertaken for patients <18 years of age, weighing >10 kg with isolated ducts <3 mm in diameter. Baseline, procedural, and outcome characteristics were compared in an intention-to-treat analysis according to randomization group. From 40 consecutively screened patients, 2 were not enrolled due to a ductal diameter of >3 mm on initial aortography, 38 patients were randomized to either the DU (n ؍ 20) or WC (n ؍ 18) groups. The groups did not differ significantly with respect to age, weight, gender, duct size, type, or branch pulmonary artery diameters. Crossover occurred only in the DU group, where 4 patients (20%) had a ductal diameter of <1 mm and could not be entered for umbrella placement. All remaining DU group patients had ductal diameters of >1.3 mm (p <0.0001). There were no embolizations or secondary implants in the DU group, but in the WC group there was 1 early and 1 late embolization, with 6 patients (33%) with >2 coils. Mean times for the procedure (DU 68 ؎ 19 minutes; WC 65 ؎ 27 minutes; p ؍ 0.70) and fluoroscopy (DU 14 ؎ 4 minutes; WC 11 ؎ 6 minutes; p ؍ 0.22) did not differ significantly. Angiographic duct closure was documented in 4 of 13 patients (31%) of the DU group and 4 of 18 patients (22%) of the WC group (p ؍ 0.69). Combined with an echocardiogram, closure in 11of 17 patients with DU (65%) and 13 of 18 patients with WC (72%) (p ؍ 0.64) was documented before hospital discharge. One WC group patient received thrombolytic therapy for a femoral artery thrombus. Follow-up at a median of 6.5 months (range 3.2 to 37) showed closure by Doppler echocardiography in 15 of 19 patients with DU (79%) versus 14 of 18 patients with WC (78%) (p ؍ 1.0). Thus, with a tendency toward similar procedural characteristics and outcomes, the higher cost of the DU system compared with coil implants favors the use of coils for closure of the small arterial duct. ᮊ2001 by Excerpta Medica, Inc.
larged redundant right atria.'9 Additionally, the presence of a pacemaker lead may contribute to ... more larged redundant right atria.'9 Additionally, the presence of a pacemaker lead may contribute to thrombus formation." The development of a right atria1 thrombus and possible pulmonary artery emboli can result in adverse hemodynamic consequences in a patient with a Fontan circulation. It seems prudent to routinely administer anticoagulant therapy to patients with transvenous leads. Additionally, in patients with an atria1 level right-to-left shunt via a fenestration, adjustable atria1 septal defect, or baffle leak, there is the potential for paradoxical emboli; therefore, these patients should not receive transvenous leads.
Journal of the American College of Cardiology, 2004
The purpose of this study was to examine the safety and efficacy of interventional catheterizatio... more The purpose of this study was to examine the safety and efficacy of interventional catheterization performed early after congenital heart surgery. BACKGROUND Transcatheter interventions performed in the early postoperative period are viewed as high risk. To date, there have been limited published data regarding these procedures. METHODS All catheterizations performed within six weeks after congenital heart surgery between August 1995 and January 2001 were retrospectively reviewed. A cardiac anesthesiologist, cardiac intensivist, cardiac surgeon, and operating room team were available for all cases. Interventional procedures were performed based on clinical indications, regardless of the time elapsed from surgery. RESULTS Sixty-two patients, median age four months (2 days to 11 years), weight 4.7 kg (2.3 to 45 kg), underwent 66 catheterizations on median postoperative day 9 (0 to 42 days). Thirty-five cases involved 50 interventional procedures. Nine patients required extracorporeal cardiopulmonary support. Success rates by procedure were: angioplasty, 100%; stent implantation, 87%; vascular/septal occlusion, 100%; and palliative pulmonary valvotomy, 75%. Complications included stent migration (one patient), cerebral vascular injury (one patient), and left pulmonary artery stenosis (one patient). Thirty procedures involved angioplasty or stent implantation, including 26 involving a recently created suture line. Suture disruption or trans-mural vascular tears were not observed. There was no procedural mortality. Thirty-day survival for patients undergoing intervention was 83%. CONCLUSIONS Transcatheter interventions can be successfully performed in the early postoperative period. These procedures can have a positive impact on patient outcome; however, they should be performed only by a pediatric interventional cardiologist supported by a multidisciplinary team.
A possibility to search for a heavy isosinglet (sterile) neutrino using its decay mode ν s → l ± ... more A possibility to search for a heavy isosinglet (sterile) neutrino using its decay mode ν s → l ± + 2 jets in the S -channel production pp → W * + X → l ± ν s + X in the CMS experiment is studied. The only assumption about the heavy neutrino is its nonzero mixing with ν e or ν µ . The corresponding CMS discovery potential expressed in terms of the heavy neutrino mass and the mixing parameter between the heavy and light neutrino is determined. It is shown that the heavy neutrino with a mass up to 800 GeV could be detected in CMS. We also investigate the production of the heavy neutrino N l mixed with ν e and/or ν µ in the SU C (3) ⊗ SU L (2) ⊗ SU R (2) ⊗ U (1) model through the reaction pp → W R + X → l ± N l + X with the same heavy neutrino decay channel as above. We find that for M WR < 3 T eV it is possible to discover the heavy neutrino with a mass up to 0.75 • M WR .
Ó The Author(s) 2011. This article is published with open access at Springerlink.com Abstract Our... more Ó The Author(s) 2011. This article is published with open access at Springerlink.com Abstract Our programmatic approach to the Fontan operation has evolved to include using an extracardiac conduit with aggressive presumptive treatment of associated lesions either in the catheterization laboratory or the operating room. Fenestration is used selectively based on hemodynamics, anatomy, and presence of associated lesions. We reviewed our experience to determine the effectiveness and outcome of this strategy and to assess the cumulative trauma to the patients. The records of 137 consecutive patients who underwent Fontan at Miami Children’s Hospital from 1995 to 2008 were reviewed. At mean follow up of 5.76 years, freedom from death or transplantation is 94.2 % (129/137). Median age at operation was 4.6 years. Longer length of stay correlated with older operative age (P = 0.0056). Pacemakers were implanted in 11.7 % (16/137). Additional (not pre-Glenn or pre-Fontan) interventional cathete...
Catheterization and cardiovascular diagnosis, 1993
Between January 1990 and February 1992, 5 asymptomatic patients were identified with hypoplasia o... more Between January 1990 and February 1992, 5 asymptomatic patients were identified with hypoplasia of the aortic isthmus at the time of cardiac catheterization for closure of a small patent ductus arteriosus. Isthmal diameters measured from lateral aortograms were 62 +/- 11% of age-matched controls. All patients had a small communication occluded with a 12 mm device and remained asymptomatic at 6-30 months follow up. Residual shunting was demonstrated by color Doppler in 2 patients. No child has developed an arm-leg systolic blood pressure gradient or systemic hypertension. Following device placement, Doppler interrogation across the isthmus in 2 patients demonstrated a velocity shift of 2.1 m/s. Transcatheter occlusion of the patient ductus arteriosus associated with mild isthmal hypoplasia of the aortic arch appears safe and effective and does not result in a clinically significant impairment to isthmal flow in short-term follow-up.
To review the outcomes of transcatheter closure of atrial septal defects using the Cardio-Seal im... more To review the outcomes of transcatheter closure of atrial septal defects using the Cardio-Seal implant. A prospective interventional study. Tertiary referral centre. The first 50 patients (median age 9.7 years) who underwent attempted percutaneous occlusion. Procedures were done under general anaesthesia and transoesophageal guidance between December 1996 and July 1998. Success of deployment, complications, and assessment of right ventricular end diastolic diameter, septal wall motion, and occlusion status by echocardiography. The median balloon stretched diameter was 14 mm. Multiple atrial septal defects were present in 11 patients (22%) and a deficient atrial rim (< 4 mm) in 19 (38%). In four patients (8%), a second device was implanted after removal of an initially malpositioned first implant. There were no significant immediate complications. All patients except one were discharged within 24 hours. At the latest follow up (mean 9.9 months) a small shunt was present in 23 pati...
Catheterization and cardiovascular diagnosis, 1993
Between January 1990 and February 1992, 5 asymptomatic patients were identified with hypoplasia o... more Between January 1990 and February 1992, 5 asymptomatic patients were identified with hypoplasia of the aortic isthmus at the time of cardiac catheterization for closure of a small patent ductus arteriosus. Isthmal diameters measured from lateral aortograms were 62 +/- 11% of age-matched controls. All patients had a small communication occluded with a 12 mm device and remained asymptomatic at 6-30 months follow up. Residual shunting was demonstrated by color Doppler in 2 patients. No child has developed an arm-leg systolic blood pressure gradient or systemic hypertension. Following device placement, Doppler interrogation across the isthmus in 2 patients demonstrated a velocity shift of 2.1 m/s. Transcatheter occlusion of the patient ductus arteriosus associated with mild isthmal hypoplasia of the aortic arch appears safe and effective and does not result in a clinically significant impairment to isthmal flow in short-term follow-up.
The Gianturco spring coil has been employed in the setting of the small arterial duct and for reo... more The Gianturco spring coil has been employed in the setting of the small arterial duct and for reocclusion of residual shunts; the ability to manipulate the coil is advantageous for optimal results. This case study reports an associated complication of unraveling of the coil. Careful attention to coil appearance during manipulation and the use of 0.038-inch coils may reduce this risk.
Catheterization and Cardiovascular Diagnosis, 1997
The clinical impact of transcatheter perforation and dilatation of the right ventricular outflow ... more The clinical impact of transcatheter perforation and dilatation of the right ventricular outflow tract in neonates with pulmonary atresia and intact ventricular septum was reviewed. Between April 1992 and December 1994, 8 neonates underwent transcatheter perforation of the right ventricular outflow tract. Radiofrequency energy was employed in 6 patients and wire perforation in 2 patients. Mean patient age at intervention was 1.9 +/- 0.6 days and weight 3.4 +/- 0.5 kg. Median tricuspid valve annulus was 10.9 mm (range: 4.0-13.0 mm) and Z-value -0.85 (range: -4.5-1.0). The mean right ventricular systolic pressure fell from 117 +/- 16 to 55 +/- 15 mm Hg (P &lt; 0.0001), and the right ventricular to aortic pressure ratio decreased from 1.81 +/- 0.33 to 0.82 +/- 0.28 (P &lt; 0.0001). The arterial duct was patent in all. No acute complications occurred. Aortopulmonary shunts were performed in 7 patients at a median 6 days (range: 3-23 days) following catheterization. One patient developed sepsis and died after surgical resection of infected tissue, while a second patient died of a blocked aortopulmonary shunt 17 months following discharge. Median follow-up for the 6 surviving patients was 8 months (range: 4-32 months). One patient has achieved and a second is awaiting biventricular repair. Transcatheter perforation appears to be a promising form of therapy in selected patients with pulmonary atresia, and potentially facilitates algorithms leading to a biventricular repair.
Two children (a 9 year old boy and a 2.5 year old girl) with coronary artery fistulae communicati... more Two children (a 9 year old boy and a 2.5 year old girl) with coronary artery fistulae communicating with the right ventricle underwent successful transcatheter occlusion using an antegrade technique. A Rashkind double umbrella device was used in one case and an Amplatzer duct occluder in the other.
Objective-To describe unusual venous communications from the right to the left atrium resulting i... more Objective-To describe unusual venous communications from the right to the left atrium resulting in cyanosis after the modified Fontan procedure, and their management with transcatheter occlusion. Methods-Between September 1992 and November 1994, eight patients were assessed for persistent cyanosis after a modified Fontan procedure. Desaturation was found to be caused by unusual venous shunts originating at atrial level, and transcatheter occlusion with either a double umbrella or coil was attempted. Results-Three types of venous channels were identified. The first type of communication consisted of thin long tortuous channels originating from the right atrial
Objectives-To review efficacy and safety of endovascular stent implants in children < 1 year of a... more Objectives-To review efficacy and safety of endovascular stent implants in children < 1 year of age with congenital heart lesions. Design-Retrospective study of patients in a tertiary care setting. Patients-26 children (median age of 47 months, range 2 days to 1 year) with various vascular obstructive lesions. Intervention-Percutaneous or intraoperative implantation of balloon expandable endovascular stents. Results-Optimal stent placement was obtained in 31 of the 37 deployed implants. Complications resulted primarily from stent malpositioning and one episode of bleeding at a puncture site. Stent implantation in three patients with a restrictive arterial duct allowed for patency and five patients with conduit stenosis had mean (SD) right ventricule to systemic artery pressure ratios falling from 0 99 (0.20) to 0 52 (0.18) (P < 0.05). In 10 patients with pulmonary artery stenosis, the mean vessel diameter increased from 2-8 (0.9) mm to 5 8 (1.4) mm (P << 0.001). No clinical improvement was seen in two patients because of diffuse hypoplasia of the pulmonary vessels. Nine of 10 patients with miscellaneous obstructive lesions improved clinically. Recatheterisation was performed in 19 patients (median 8 months, range 12 days to 28 months) and 11 patients required redilatation (17 stents). Conclusions-Stent implantation is technically feasible in infants and under specific circumstances may provide an alternative to surgical palliation or avoid reoperation. The long term impact on clinical course, however, involves further interventions directed at stent management.
Objective: To review the evolution of transcatheter patent ductus arteriosus (PDA) occlusion tech... more Objective: To review the evolution of transcatheter patent ductus arteriosus (PDA) occlusion techniques and results. Methods: A single institution, retrospective review including all patients with intention to close a PDA from 1991 to 1998, with no exclusions. Results: ...
Obstruction of the reconstructed aortic arch, or the neoaortic arch, is now known to be an import... more Obstruction of the reconstructed aortic arch, or the neoaortic arch, is now known to be an important factor increasing mortality after the Norwood operation for hypoplastic left heart syndrome. Transcatheter balloon angioplasty has been shown to provide effective relief of both native aortic coarctation and obstructions of the aortic arch occurring subsequent to therapeutic intervention. We sought to determine the outcomes of balloon angioplasty used as an initial treatment for obstruction of the neoaortic arch occurring after the Norwood operation. We gathered the characteristics of 58 patients with such obstruction from 8 institutions, noting procedural factors and outcomes of initial balloon dilation. Obstruction occurred at a median interval of 4 months, with a range from 1.5 months to 6.3 years, after a Norwood operation. Ventricular dysfunction was present before dilation in 13 patients. Mean peak to peak systolic pressure gradients were acutely reduced from 31±20 mm Hg to 6±9...
We describe what is, to the best of our knowledge, a previously unreported association in patient... more We describe what is, to the best of our knowledge, a previously unreported association in patients with similar facial features, skin and joint laxity, of lengthening and tortuosity of systemic, pulmonary and coronary vessels. We evaluated 12 patients with similar phenotypes, from eight different families. Detailed echocardiographic and angiographic evaluations were performed in all, and biopsies of the skin in seven. All patients have elongated facies, prominent ears, micrognathia and laxity of their joints. Angiographic pictures showed a varying degree of lengthening and tortuosity of systemic, pulmonary, and coronary arteries. Pulsatile carotid arteries formed cervical masses in 2 patients, and three had severe renal arterial stenoses. All showed varying degrees of branch and peripheral pulmonary arterial stenosis, necessitating placement of stents in six. Biopsy of the skin proved normal in all seven patients studied, thus excluding cutis laxa, Ehlers-Danlos and Marfan syndromes. The constellation of abnormalities suggests a genetic syndrome of connective tissue etiology. Further genetic studies, and gene mapping, are underway.
The Journal of Thoracic and Cardiovascular Surgery, 1995
The use of endovascular devices as an adjunct to repair of congenital heart anomalies represents ... more The use of endovascular devices as an adjunct to repair of congenital heart anomalies represents a novel but unproven therapeutic approach. Intraoperative implantation of pulmonary arterial stents (5 to 15 mm diameter) was done in 11 patients with pulmonary atresia with ventricular septal defect (n = 4), classic tetralogy of Fallot (n = 2), truncus arteriosus (n = 1), hypoplastic left heart syndrome (stage II [n = 1] and stage III In = 1] Norwood procedure), and miscellaneous pulmonary arterial stenoses (n = 3), as well as in patients with congenital (n = 1) and postoperative (n = 3) pulmonary venous osbstruction and in 1 patient with combined pulmonary arteria~ and venous obstruction. The stents were effective at achieving immediate patency in all patients. There were two early deaths, one related to acute thrombosis of a small-diameter left pulmonary artery stent. Reintervention because of stentrelated pulmonary arterial stenosis was frequently necessary. In five of seven patients who survived more than I month after implantation of stent size 8 mm or smaller severe stent-related pulmonary arterial obstruction developed. In four of the five patients with pulmonary vein stent implantation intractable obstruction developed, resulting in death in all three patients who had bilateral pulmonary vein stent implantation. Intraoperative occlusion of apical muscular ventricular septal defect with use of a clamshell device inserted from the right atrial approach was accomplished in four patients. One patient who underwent associated aortic arch reconstruction died as a result of left ventricular hypoplasia. The results in the remaining three patients were favorable on the basis of absence of significant late residual intraventricular shunting, left ventricular dysfunction, or arrhythmia. We conclude that recurrent intraluminal obstruction as a result of neointimal hyperplasia appears to be an eventual certainty in currently designed small-diameter endovascular stents. For this reason, we would recommend standard surgical techniques for repair of obstructive lesions of the pulmonary arterial confluence to maximize growth potential. Device occlusion of muscular ventricular septal defects is feasible but probably only indicated for complex cases of ventricular septal deficiency that otherwise necessitate a left ventriculotomy.
A randomized trial of arterial duct occlusion with a double umbrella (DU) or wire coil (WC) was u... more A randomized trial of arterial duct occlusion with a double umbrella (DU) or wire coil (WC) was undertaken for patients <18 years of age, weighing >10 kg with isolated ducts <3 mm in diameter. Baseline, procedural, and outcome characteristics were compared in an intention-to-treat analysis according to randomization group. From 40 consecutively screened patients, 2 were not enrolled due to a ductal diameter of >3 mm on initial aortography, 38 patients were randomized to either the DU (n ؍ 20) or WC (n ؍ 18) groups. The groups did not differ significantly with respect to age, weight, gender, duct size, type, or branch pulmonary artery diameters. Crossover occurred only in the DU group, where 4 patients (20%) had a ductal diameter of <1 mm and could not be entered for umbrella placement. All remaining DU group patients had ductal diameters of >1.3 mm (p <0.0001). There were no embolizations or secondary implants in the DU group, but in the WC group there was 1 early and 1 late embolization, with 6 patients (33%) with >2 coils. Mean times for the procedure (DU 68 ؎ 19 minutes; WC 65 ؎ 27 minutes; p ؍ 0.70) and fluoroscopy (DU 14 ؎ 4 minutes; WC 11 ؎ 6 minutes; p ؍ 0.22) did not differ significantly. Angiographic duct closure was documented in 4 of 13 patients (31%) of the DU group and 4 of 18 patients (22%) of the WC group (p ؍ 0.69). Combined with an echocardiogram, closure in 11of 17 patients with DU (65%) and 13 of 18 patients with WC (72%) (p ؍ 0.64) was documented before hospital discharge. One WC group patient received thrombolytic therapy for a femoral artery thrombus. Follow-up at a median of 6.5 months (range 3.2 to 37) showed closure by Doppler echocardiography in 15 of 19 patients with DU (79%) versus 14 of 18 patients with WC (78%) (p ؍ 1.0). Thus, with a tendency toward similar procedural characteristics and outcomes, the higher cost of the DU system compared with coil implants favors the use of coils for closure of the small arterial duct. ᮊ2001 by Excerpta Medica, Inc.
larged redundant right atria.'9 Additionally, the presence of a pacemaker lead may contribute to ... more larged redundant right atria.'9 Additionally, the presence of a pacemaker lead may contribute to thrombus formation." The development of a right atria1 thrombus and possible pulmonary artery emboli can result in adverse hemodynamic consequences in a patient with a Fontan circulation. It seems prudent to routinely administer anticoagulant therapy to patients with transvenous leads. Additionally, in patients with an atria1 level right-to-left shunt via a fenestration, adjustable atria1 septal defect, or baffle leak, there is the potential for paradoxical emboli; therefore, these patients should not receive transvenous leads.
Journal of the American College of Cardiology, 2004
The purpose of this study was to examine the safety and efficacy of interventional catheterizatio... more The purpose of this study was to examine the safety and efficacy of interventional catheterization performed early after congenital heart surgery. BACKGROUND Transcatheter interventions performed in the early postoperative period are viewed as high risk. To date, there have been limited published data regarding these procedures. METHODS All catheterizations performed within six weeks after congenital heart surgery between August 1995 and January 2001 were retrospectively reviewed. A cardiac anesthesiologist, cardiac intensivist, cardiac surgeon, and operating room team were available for all cases. Interventional procedures were performed based on clinical indications, regardless of the time elapsed from surgery. RESULTS Sixty-two patients, median age four months (2 days to 11 years), weight 4.7 kg (2.3 to 45 kg), underwent 66 catheterizations on median postoperative day 9 (0 to 42 days). Thirty-five cases involved 50 interventional procedures. Nine patients required extracorporeal cardiopulmonary support. Success rates by procedure were: angioplasty, 100%; stent implantation, 87%; vascular/septal occlusion, 100%; and palliative pulmonary valvotomy, 75%. Complications included stent migration (one patient), cerebral vascular injury (one patient), and left pulmonary artery stenosis (one patient). Thirty procedures involved angioplasty or stent implantation, including 26 involving a recently created suture line. Suture disruption or trans-mural vascular tears were not observed. There was no procedural mortality. Thirty-day survival for patients undergoing intervention was 83%. CONCLUSIONS Transcatheter interventions can be successfully performed in the early postoperative period. These procedures can have a positive impact on patient outcome; however, they should be performed only by a pediatric interventional cardiologist supported by a multidisciplinary team.
A possibility to search for a heavy isosinglet (sterile) neutrino using its decay mode ν s → l ± ... more A possibility to search for a heavy isosinglet (sterile) neutrino using its decay mode ν s → l ± + 2 jets in the S -channel production pp → W * + X → l ± ν s + X in the CMS experiment is studied. The only assumption about the heavy neutrino is its nonzero mixing with ν e or ν µ . The corresponding CMS discovery potential expressed in terms of the heavy neutrino mass and the mixing parameter between the heavy and light neutrino is determined. It is shown that the heavy neutrino with a mass up to 800 GeV could be detected in CMS. We also investigate the production of the heavy neutrino N l mixed with ν e and/or ν µ in the SU C (3) ⊗ SU L (2) ⊗ SU R (2) ⊗ U (1) model through the reaction pp → W R + X → l ± N l + X with the same heavy neutrino decay channel as above. We find that for M WR < 3 T eV it is possible to discover the heavy neutrino with a mass up to 0.75 • M WR .
Ó The Author(s) 2011. This article is published with open access at Springerlink.com Abstract Our... more Ó The Author(s) 2011. This article is published with open access at Springerlink.com Abstract Our programmatic approach to the Fontan operation has evolved to include using an extracardiac conduit with aggressive presumptive treatment of associated lesions either in the catheterization laboratory or the operating room. Fenestration is used selectively based on hemodynamics, anatomy, and presence of associated lesions. We reviewed our experience to determine the effectiveness and outcome of this strategy and to assess the cumulative trauma to the patients. The records of 137 consecutive patients who underwent Fontan at Miami Children’s Hospital from 1995 to 2008 were reviewed. At mean follow up of 5.76 years, freedom from death or transplantation is 94.2 % (129/137). Median age at operation was 4.6 years. Longer length of stay correlated with older operative age (P = 0.0056). Pacemakers were implanted in 11.7 % (16/137). Additional (not pre-Glenn or pre-Fontan) interventional cathete...
Catheterization and cardiovascular diagnosis, 1993
Between January 1990 and February 1992, 5 asymptomatic patients were identified with hypoplasia o... more Between January 1990 and February 1992, 5 asymptomatic patients were identified with hypoplasia of the aortic isthmus at the time of cardiac catheterization for closure of a small patent ductus arteriosus. Isthmal diameters measured from lateral aortograms were 62 +/- 11% of age-matched controls. All patients had a small communication occluded with a 12 mm device and remained asymptomatic at 6-30 months follow up. Residual shunting was demonstrated by color Doppler in 2 patients. No child has developed an arm-leg systolic blood pressure gradient or systemic hypertension. Following device placement, Doppler interrogation across the isthmus in 2 patients demonstrated a velocity shift of 2.1 m/s. Transcatheter occlusion of the patient ductus arteriosus associated with mild isthmal hypoplasia of the aortic arch appears safe and effective and does not result in a clinically significant impairment to isthmal flow in short-term follow-up.
To review the outcomes of transcatheter closure of atrial septal defects using the Cardio-Seal im... more To review the outcomes of transcatheter closure of atrial septal defects using the Cardio-Seal implant. A prospective interventional study. Tertiary referral centre. The first 50 patients (median age 9.7 years) who underwent attempted percutaneous occlusion. Procedures were done under general anaesthesia and transoesophageal guidance between December 1996 and July 1998. Success of deployment, complications, and assessment of right ventricular end diastolic diameter, septal wall motion, and occlusion status by echocardiography. The median balloon stretched diameter was 14 mm. Multiple atrial septal defects were present in 11 patients (22%) and a deficient atrial rim (< 4 mm) in 19 (38%). In four patients (8%), a second device was implanted after removal of an initially malpositioned first implant. There were no significant immediate complications. All patients except one were discharged within 24 hours. At the latest follow up (mean 9.9 months) a small shunt was present in 23 pati...
Catheterization and cardiovascular diagnosis, 1993
Between January 1990 and February 1992, 5 asymptomatic patients were identified with hypoplasia o... more Between January 1990 and February 1992, 5 asymptomatic patients were identified with hypoplasia of the aortic isthmus at the time of cardiac catheterization for closure of a small patent ductus arteriosus. Isthmal diameters measured from lateral aortograms were 62 +/- 11% of age-matched controls. All patients had a small communication occluded with a 12 mm device and remained asymptomatic at 6-30 months follow up. Residual shunting was demonstrated by color Doppler in 2 patients. No child has developed an arm-leg systolic blood pressure gradient or systemic hypertension. Following device placement, Doppler interrogation across the isthmus in 2 patients demonstrated a velocity shift of 2.1 m/s. Transcatheter occlusion of the patient ductus arteriosus associated with mild isthmal hypoplasia of the aortic arch appears safe and effective and does not result in a clinically significant impairment to isthmal flow in short-term follow-up.
The Gianturco spring coil has been employed in the setting of the small arterial duct and for reo... more The Gianturco spring coil has been employed in the setting of the small arterial duct and for reocclusion of residual shunts; the ability to manipulate the coil is advantageous for optimal results. This case study reports an associated complication of unraveling of the coil. Careful attention to coil appearance during manipulation and the use of 0.038-inch coils may reduce this risk.
Catheterization and Cardiovascular Diagnosis, 1997
The clinical impact of transcatheter perforation and dilatation of the right ventricular outflow ... more The clinical impact of transcatheter perforation and dilatation of the right ventricular outflow tract in neonates with pulmonary atresia and intact ventricular septum was reviewed. Between April 1992 and December 1994, 8 neonates underwent transcatheter perforation of the right ventricular outflow tract. Radiofrequency energy was employed in 6 patients and wire perforation in 2 patients. Mean patient age at intervention was 1.9 +/- 0.6 days and weight 3.4 +/- 0.5 kg. Median tricuspid valve annulus was 10.9 mm (range: 4.0-13.0 mm) and Z-value -0.85 (range: -4.5-1.0). The mean right ventricular systolic pressure fell from 117 +/- 16 to 55 +/- 15 mm Hg (P &lt; 0.0001), and the right ventricular to aortic pressure ratio decreased from 1.81 +/- 0.33 to 0.82 +/- 0.28 (P &lt; 0.0001). The arterial duct was patent in all. No acute complications occurred. Aortopulmonary shunts were performed in 7 patients at a median 6 days (range: 3-23 days) following catheterization. One patient developed sepsis and died after surgical resection of infected tissue, while a second patient died of a blocked aortopulmonary shunt 17 months following discharge. Median follow-up for the 6 surviving patients was 8 months (range: 4-32 months). One patient has achieved and a second is awaiting biventricular repair. Transcatheter perforation appears to be a promising form of therapy in selected patients with pulmonary atresia, and potentially facilitates algorithms leading to a biventricular repair.
Two children (a 9 year old boy and a 2.5 year old girl) with coronary artery fistulae communicati... more Two children (a 9 year old boy and a 2.5 year old girl) with coronary artery fistulae communicating with the right ventricle underwent successful transcatheter occlusion using an antegrade technique. A Rashkind double umbrella device was used in one case and an Amplatzer duct occluder in the other.
Objective-To describe unusual venous communications from the right to the left atrium resulting i... more Objective-To describe unusual venous communications from the right to the left atrium resulting in cyanosis after the modified Fontan procedure, and their management with transcatheter occlusion. Methods-Between September 1992 and November 1994, eight patients were assessed for persistent cyanosis after a modified Fontan procedure. Desaturation was found to be caused by unusual venous shunts originating at atrial level, and transcatheter occlusion with either a double umbrella or coil was attempted. Results-Three types of venous channels were identified. The first type of communication consisted of thin long tortuous channels originating from the right atrial
Objectives-To review efficacy and safety of endovascular stent implants in children < 1 year of a... more Objectives-To review efficacy and safety of endovascular stent implants in children < 1 year of age with congenital heart lesions. Design-Retrospective study of patients in a tertiary care setting. Patients-26 children (median age of 47 months, range 2 days to 1 year) with various vascular obstructive lesions. Intervention-Percutaneous or intraoperative implantation of balloon expandable endovascular stents. Results-Optimal stent placement was obtained in 31 of the 37 deployed implants. Complications resulted primarily from stent malpositioning and one episode of bleeding at a puncture site. Stent implantation in three patients with a restrictive arterial duct allowed for patency and five patients with conduit stenosis had mean (SD) right ventricule to systemic artery pressure ratios falling from 0 99 (0.20) to 0 52 (0.18) (P < 0.05). In 10 patients with pulmonary artery stenosis, the mean vessel diameter increased from 2-8 (0.9) mm to 5 8 (1.4) mm (P << 0.001). No clinical improvement was seen in two patients because of diffuse hypoplasia of the pulmonary vessels. Nine of 10 patients with miscellaneous obstructive lesions improved clinically. Recatheterisation was performed in 19 patients (median 8 months, range 12 days to 28 months) and 11 patients required redilatation (17 stents). Conclusions-Stent implantation is technically feasible in infants and under specific circumstances may provide an alternative to surgical palliation or avoid reoperation. The long term impact on clinical course, however, involves further interventions directed at stent management.
Objective: To review the evolution of transcatheter patent ductus arteriosus (PDA) occlusion tech... more Objective: To review the evolution of transcatheter patent ductus arteriosus (PDA) occlusion techniques and results. Methods: A single institution, retrospective review including all patients with intention to close a PDA from 1991 to 1998, with no exclusions. Results: ...
Obstruction of the reconstructed aortic arch, or the neoaortic arch, is now known to be an import... more Obstruction of the reconstructed aortic arch, or the neoaortic arch, is now known to be an important factor increasing mortality after the Norwood operation for hypoplastic left heart syndrome. Transcatheter balloon angioplasty has been shown to provide effective relief of both native aortic coarctation and obstructions of the aortic arch occurring subsequent to therapeutic intervention. We sought to determine the outcomes of balloon angioplasty used as an initial treatment for obstruction of the neoaortic arch occurring after the Norwood operation. We gathered the characteristics of 58 patients with such obstruction from 8 institutions, noting procedural factors and outcomes of initial balloon dilation. Obstruction occurred at a median interval of 4 months, with a range from 1.5 months to 6.3 years, after a Norwood operation. Ventricular dysfunction was present before dilation in 13 patients. Mean peak to peak systolic pressure gradients were acutely reduced from 31±20 mm Hg to 6±9...
We describe what is, to the best of our knowledge, a previously unreported association in patient... more We describe what is, to the best of our knowledge, a previously unreported association in patients with similar facial features, skin and joint laxity, of lengthening and tortuosity of systemic, pulmonary and coronary vessels. We evaluated 12 patients with similar phenotypes, from eight different families. Detailed echocardiographic and angiographic evaluations were performed in all, and biopsies of the skin in seven. All patients have elongated facies, prominent ears, micrognathia and laxity of their joints. Angiographic pictures showed a varying degree of lengthening and tortuosity of systemic, pulmonary, and coronary arteries. Pulsatile carotid arteries formed cervical masses in 2 patients, and three had severe renal arterial stenoses. All showed varying degrees of branch and peripheral pulmonary arterial stenosis, necessitating placement of stents in six. Biopsy of the skin proved normal in all seven patients studied, thus excluding cutis laxa, Ehlers-Danlos and Marfan syndromes. The constellation of abnormalities suggests a genetic syndrome of connective tissue etiology. Further genetic studies, and gene mapping, are underway.
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Papers by D.g Nykanen