Papers by Patrick Verhorst
Netherlands heart journal : monthly journal of the Netherlands Society of Cardiology and the Netherlands Heart Foundation, 2006
Severe regurgitation due to perforation of the mitral–aortic intervalvular fibrosa 3 years
Journal of the American College of Cardiology, 2012
Journal of the American College of Cardiology, 2013
This article has been selected as the month's JACC Journal CME activity. Accreditation and Design... more This article has been selected as the month's JACC Journal CME activity. Accreditation and Designation Statement The American College of Cardiology Foundation (ACCF) is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians. The ACCF designates this Journal-based CME activity for a maximum of 1 AMA PRA Category 1 Credit(s). Physicians should only claim credit commensurate with the extent of their participation in the activity. Method of Participation and Receipt of CME Certificate To obtain credit for JACC CME, you must: 1. Be an ACC member or JACC subscriber. 2. Carefully read the CME-designated article available online and in this issue of the journal. 3. Answer the post-test questions. At least 2 out of the 3 questions provided must be answered correctly to obtain CME credit. 4. Complete a brief evaluation. 5. Claim your CME credit and receive your certificate electronically by following the instructions given at the conclusion of the activity. CME Objective for This Article: At the conclusion of this activity, the learner should be able to compare survival of asymptomatic patients with prior revascularization and ischemia, who subsequently underwent repeat revascularization or medical therapy.
The International Journal of Cardiovascular Imaging, 2010
Volumetric radiofrequency-based intravascular ultrasound (RF-IVUS) data of coronary segments are ... more Volumetric radiofrequency-based intravascular ultrasound (RF-IVUS) data of coronary segments are increasingly used as endpoints in serial trials of novel anti-atherosclerotic therapies. In a relatively time-consuming process, vessel and lumen contours are defined; these contours are first automatically detected, then visually checked, and finally (in most cases) manually edited to generate reliable volumetric data of vessel geometry and plaque composition. Reduction in number of cross-sectional images for volumetric analysis could save analysis time but may also increase measurement variability of volumetric data. To assess whether a 50% reduction in number of frames per segment (every second frame) alters the reproducibility of volumetric measurements, we performed repeated RF-IVUS analyses of 15 coronary segments with mild-tomoderate atherosclerosis (20.2 ± 0.2 mm-long segments with 46 ± 13% plaque burden). Volumes were calculated based on a total of 731 image frames. Reducing the number of cross-sectional image frames for volumetric measurements saved analysis time (38 ± 9 vs. 68 ± 17 min/segment; P \ 0.0001) and resulted for only a few parameters in (borderline) significant but mild differences versus measurements based on all frames (fibrous volume, P \ 0.05; necrotic-core volume, P = 0.07). Compared to the intra-observer variability, there was a mild increase in measurement variability for most geometrical and compositional volumetric RF-IVUS parameters. In RF-IVUS studies of mild-to-moderate coronary disease, analyzing less image frames saved analysis time, left most volumetric parameters greatly unaffected, and resulted in a no more than mild increase in measurement variability of volumetric data. Keywords Intravascular ultrasound Á Radiofrequency Á Virtual histology Á Plaque composition Á Necrotic core Á Vulnerable plaque Á IVUS Á VH-IVUS Á Reproducibility Á Variability Á Atherosclerosis Á Coronary artery disease Á Coronary vessels Abbreviations IVUS Intravascular ultrasound RF Radiofrequency
The International Journal of Cardiovascular Imaging, 2006
We present a case of a 66-year-old patient with infective endocarditis of an aortic valve biopros... more We present a case of a 66-year-old patient with infective endocarditis of an aortic valve bioprosthesis with major dehiscence and extensive ''rocking motion'' but without any diastolic paravalvular regurgitation as assessed with radiography and transesophageal echocardiography.
The International Journal of Cardiovascular Imaging, 2006
Serial intravascular ultrasound (IVUS) measurements of coronary vessel dimensions are major endpo... more Serial intravascular ultrasound (IVUS) measurements of coronary vessel dimensions are major endpoints of studies focusing on pharmacological interventions, efficiency of drug eluting stents, and vascular remodeling. In serial studies measurement variability among different IVUS devices may cause substantial misinterpretation and error. We analyzed 33 human coronary plaques in vitro using two different IVUS systems (mechanical IVUS system with a 40 MHz Atlantis SR catheter; solid-state electronic IVUS system with a 20 MHz Invision catheter) and repeatedly measured the total vessel, lumen, and plaque + media cross-sectional area and plaque burden (plaque + media area divided by total vessel area). Between the ''raw'' measurements made by the two devices, there was a significant difference for both plaque + media area (2.35-1.86 mm 2 , P\0:01) and plaque burden (5.39-3.68%, P\0:05). Measurements were then corrected by use of recently introduced calibration formulas; as a result the differences decreased significantly for all IVUS parameters measured (P\0:0001). After correction, the remaining differences between the corrected mechanical and solid-state IVUS measurements similar to differences between repeated measurements with the same IVUS device (i.e., the intraobserver variability). Thus, in serial studies the use of different IVUS devices at index and follow-up procedure may introduce a substantial error as a result of system-related differences. The application of dedicated calibration formulas allows for correction for these differences by decreasing such differences to the level of intraobserver variability.
International Journal of Cardiology, 1996
This report describes a 34-year-old female with an exercise-induced atrioventricular block result... more This report describes a 34-year-old female with an exercise-induced atrioventricular block resulting from transient ischemia caused by a radiation-induced ostial stenosis of the right coronary artery. Patient first underwent coronary artery surgery with a right internal mammary artery to the right coronary artery. After 18 months she was readmitted with exercised-induced syncope due to graft occlusion. This time a successful rotablator procedure was performed on the ostial stenosis.
International Journal of Cardiovascular Imaging, 2006
Serial intravascular ultrasound (IVUS) measurements of coronary vessel dimensions are major endpo... more Serial intravascular ultrasound (IVUS) measurements of coronary vessel dimensions are major endpoints of studies focusing on pharmacological interventions, efficiency of drug eluting stents, and vascular remodeling. In serial studies measurement variability among different IVUS devices may cause substantial misinterpretation and error. We analyzed 33 human coronary plaques in vitro using two different IVUS systems (mechanical IVUS system with a 40 MHz Atlantis
European Heart Journal, 2014
European Heart Journal, 1999
Aim The purpose of this study was to investigate the role of transoesophageal echocardiography in... more Aim The purpose of this study was to investigate the role of transoesophageal echocardiography in predicting subsequent thromboembolic events in patients with atrial fibrillation. Methods and patients Transoesophageal echocardiography was performed in 88 patients with documented paroxysmal (n=53) or chronic atrial fibrillation (n=35) to assess morphological and functional predictors of thromboembolic events. Prospective selection was from patients with non-valvular atrial fibrillation who had undergone transoesophageal echocardiography because of previous thromboembolism (n=30); prior to electrical cardioversion (n=31); or for other reasons (n=27). All patients were followed up for 1 year. Results During the period of follow-up new thromboembolic events occurred in 18 of 88 patients (20%/year); 16 of these patients had a stroke and two a peripheral embolism. Univariate analysis revealed that previous thromboembolism (P<0•005; odds ratio 5•3 [CI 1•9, 12•1]), history of hypertension (P<0•01; odds ratio 4•0 [CI 1•4, 10•4), presence of left atrial spontaneous echo contrast (P<0•025; odds ratio 3•5 [CI 1•2, 10•0]), and presence of left atrial appendage peak velocity c0•20 m. s 1 (P<0•01; odds ratio 4•1 [CI 1•4, 11•6]) were significantly related to subsequent thromboembolic events. Stepwise logistic regression showed that independent predictors of thromboembolic events were: history of thromboembolism (P<0•005), history of hypertension (P<0•05) and low left atrial appendage peak velocity c0•20 m. s 1 (P<0•01). Conclusions In patients with atrial fibrillation, the presence of spontaneous echo contrast in the left atrium, and in particular a low left atrial appendage peak flow velocity, can be used to identify a subgroup of atrial fibrillation patients at either increased or decreased risk of subsequent thromboembolism, which might have important implications for anticoagulation therapy.
European Heart Journal, 2006
Glagov&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;am... more Glagov&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s histopathological observation and non-serial intravascular ultrasound studies (IVUS) concluded that compensatory coronary remodelling diminishes as 40% atherosclerotic plaque burden is reached. We tested this hypothesis with serial IVUS. Serial IVUS examinations of 46 atherosclerotic non-stenotic left main stems (18+/-8 months apart) were analysed to assess the relation between baseline plaque burden (=plaque+media area/vessel area) vs. serial remodelling (=vessel area at baseline - at follow-up). There were 25 plaques with baseline plaque burden &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;40% (30.1+/-6.6%, group A) and 21 plaques with baseline plaque burden &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or =40% (46.1+/-5.8%, group B). There was no relation between baseline plaque burden vs. subsequent changes in vessel area overall (r=0.07, P=0.7), for group A (r=0.03, P=0.6), and group B (r=0.01, P=0.8). The frequency of positive serial remodelling (vessel area increase) vs. negative or intermediate serial remodelling (no change or decrease) were similar in group A [17 (68%) vs. 8 (32%)] and group B lesions [18 (86%) vs. 3 (14%)] (P=0.2). IVUS demonstrates that serial coronary remodelling is not related to baseline plaque burden. Lesions with baseline plaque burden &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;40% may subsequently show a lack of compensation or frank arterial shrinkage, whereas lesions with baseline plaque burden &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;40% may continue to develop compensatory enlargement.
Europace, 2009
The absence of microvolt T-wave alternans (MTWA) identifies a group of patients who are at low ri... more The absence of microvolt T-wave alternans (MTWA) identifies a group of patients who are at low risk for ventricular arrhythmia or sudden cardiac death. However, in exercised assessed MTWA, 20-40% of all test results are indeterminate. We hypothesised that MTWA during pacing would yield less indeterminate results. Thirty patients with ischaemic cardiomyopathy and prior dual chamber implantable cardioverter defibrillator implantation were enrolled. All patients underwent sequential MTWA testing using an exercise (E), atrial-paced (A), and atrioventricular-paced (AV) protocol. The number of indeterminate tests was lower during pacing (A: 17%; AV: 3%) compared with exercise (37%) (E vs. A: P = 0.015, E vs. AV: P = &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). When positive and indeterminate test results were grouped as non-negative, the concordance rates between E and A, E and AV, and A and AV were 60% (kappa = 0.17), 57% (kappa = 0.058), and 70% (kappa = 0.348), respectively. If indeterminate results were excluded, agreements were 60% (kappa = 0.19), 50% (kappa = 0.129) and 67% (kappa = 0.33), respectively. Indeterminate test results are less common during pacing. However, there is a low concordance rate between test results using different protocols. This necessitates further study to determine the predictive value of each method in high risk patients with ischaemic cardiomyopathy.
Clinical Research in Cardiology, 2010
… International Journal of …, 2010
Volumetric radiofrequency-based intravascular ultrasound (RF–IVUS) data of coronary segments are ... more Volumetric radiofrequency-based intravascular ultrasound (RF–IVUS) data of coronary segments are increasingly used as endpoints in serial trials of novel anti-atherosclerotic therapies. In a relatively time-consuming process, vessel and lumen contours are defined; these contours are first automatically detected, then visually checked, and finally (in most cases) manually edited to generate reliable volumetric data of vessel geometry and plaque composition. Reduction in number of cross-sectional images for volumetric analysis could save analysis time but may also increase measurement variability of volumetric data. To assess whether a 50% reduction in number of frames per segment (every second frame) alters the reproducibility of volumetric measurements, we performed repeated RF–IVUS analyses of 15 coronary segments with mild-to-moderate atherosclerosis (20.2 ± 0.2 mm-long segments with 46 ± 13% plaque burden). Volumes were calculated based on a total of 731 image frames. Reducing the number of cross-sectional image frames for volumetric measurements saved analysis time (38 ± 9 vs. 68 ± 17 min/segment; P < 0.0001) and resulted for only a few parameters in (borderline) significant but mild differences versus measurements based on all frames (fibrous volume, P < 0.05; necrotic-core volume, P = 0.07). Compared to the intra-observer variability, there was a mild increase in measurement variability for most geometrical and compositional volumetric RF–IVUS parameters. In RF–IVUS studies of mild-to-moderate coronary disease, analyzing less image frames saved analysis time, left most volumetric parameters greatly unaffected, and resulted in a no more than mild increase in measurement variability of volumetric data.
…, 2009
Methods and results Thirty patients with ischaemic cardiomyopathy and prior dual chamber implanta... more Methods and results Thirty patients with ischaemic cardiomyopathy and prior dual chamber implantable cardioverter defibrillator implantation were enrolled. All patients underwent sequential MTWA testing using an exercise (E), atrial-paced (A), and atrioventricular-paced (AV) protocol. ...
The Annals of Thoracic Surgery, 2007
Netherlands Heart …, 2010
Background. New-generation drug-eluting stents (DES) may solve several problems encountered with ... more Background. New-generation drug-eluting stents (DES) may solve several problems encountered with first-generation DES, but there is a lack of prospective head-to-head comparisons between new-generation DES. In addition, the outcome of regulatory trials may not perfectly reflect the outcome in ‘real world’ patients.Objectives. To compare the efficacy and safety of two new-generation DES in a ‘real world’ patient population.Methods. A prospective, randomised, single-blinded clinical trial to evaluate clinical outcome after Endeavor Resolute vs. Xience V stent implantation. The primary endpoint is target vessel failure at one-year follow-up. In addition, the study comprises a two-year and an open-label five-year follow-up. (Neth Heart J 2010;18:360–4. [PMC free article] [PubMed] [Google Scholar])
Pace-pacing and Clinical Electrophysiology, 2000
To prospectively assess the incidence and clinical significance of thromboembolic complications i... more To prospectively assess the incidence and clinical significance of thromboembolic complications in patients with multiple (&amp;amp;amp;amp;amp;amp;gt; or = 3) noninfected transvenous leads; 48 consecutive patients were evaluated. Half of the patients had two ventricular leads and one atrial lead, 15 patients had two atrial leads and one ventricular lead, while 9 patients had two ventricular and two atrial leads. No additional care was provided except for aspirin (80 mg bid) and annually performed echo-Doppler studies. Clinical follow-up included signs and symptoms of subclavian and/or axillary vein thrombosis, the presence of right congestive heart failure, the number of hospital admissions, and death. Echo-Doppler studies assessed the presence of an enlarged right atrium or ventricle, right atrial or ventricular spontaneous contrast, and the presence of tricuspid regurgitation. During a total follow-up of 7.4 +/- 2.2 years there were no differences in the incidence of clinical variables as compared to age-matched controls with DDD pacemakers. The most common complication was transient venous thrombosis (mostly presenting as venous prominence 1-2 weeks after implantation), which was seen in 17% of the study group versus 15% in controls (NS). Cumulative mortality was not different in both groups (13% in the study group vs 15% in controls). No differences were present with respect to hospital admissions (1.1 +/- 0.27/year in the study group vs 1.2 +/- 0.30/year in the controls). In patients with multiple ventricular leads, tricuspid regurgitation on echo-Doppler studies was more frequent (24%) as compared to controls (4%); however, clinical signs of right heart failure were equally distributed. Thus, patients with multiple (&amp;amp;amp;amp;amp;amp;gt; or = 3) noninfected leads have no clinical adverse outcome during long-term follow-up.
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Papers by Patrick Verhorst