Papers by Krishnaswamy Chandrasekaran
Circulation, Aug 1, 1992
Background. Secondary involvement of the mitral-aortic intervalvular fibrosa and the anterior mit... more Background. Secondary involvement of the mitral-aortic intervalvular fibrosa and the anterior mitral leaflet (subaortic structures) can occur in patients with aortic valve endocarditis. The secondary involvement of these structures occurs as a result of direct extension of the infection from the aortic valve or as a result of an infected aortic regurgitant jet striking the ventricular surfaces of the mitral-aortic intervalvular fibrosa and the anterior mitral leaflet. The abscess of mitral-aortic intervalvular fibrosa can expand to form an aneurysm. Subsequently, this mitral-aortic intervalvular fibrosa aneurysm can develop a perforation and communicate with the left atrium, resulting in the systolic regurgitation of blood from the left ventricular outflow tract into the left atrium. Secondary infection can also occur on the ventricular surface of the anterior mitral leaflet and result in the formation of an aneurysm or perforation of anterior mitral leaflet. Methods and Results. This study examines the utility of transesophageal echocardiography in the detection of these subaortic complications in 55 consecutive patients with aortic valve endocarditis. A total of 24 patients (44%) had involvement of subaortic structures, including four with an abscess in the mitral-aortic intervalvular fibrosa, four with mitral-aortic intervalvular fibrosa aneurysm, seven with perforation of the mitral-aortic intervalvular fibrosa with communication into the left atrium, two with an aneurysm of the anterior mitral leaflet, and seven with perforation of the anterior mitral leaflet. The transesophageal echocardiographic findings were confirmed at surgery in 20 patients and at necropsy in two. By comparison, transthoracic echocardiography visualized these lesions in five of 24 patients (21%), including none of four with mitral-aortic intervalvular fibrosa abscesses, two of four with mitral-aortic intervalvular fibrosa aneurysms, one of seven with mitral-aortic intervalvular fibrosa perforations, one of two with anterior mitral leaflet aneurysms, and one of seven anterior mitral leaflet perforations. Eccentric mitral regurgitation-type systolic jets were noted in eight additional patients by transthoracic color flow imaging, and this finding suggested the possibility of these unusual subaortic complications. If these patients are included, then transthoracic echocardiography suggested the presence of these subaortic complications in 13 of 24 patients (54%). Conclusions. The results indicate that 1) involvement of the subaortic structures in patients with aortic valve endocarditis may be more common than previously recognized, 2) patients with aortic valve endocarditis and eccentric jets of mitral regurgitation on transthoracic echocardiography should undergo further evaluation by transesophageal echocardiography to exclude these unusual complications, 3) precise recognition of these complications is of value in the optimal medical and surgical management of these patients, and 4) these complications maybe responsible for unexplained congestive heart failure and hemodynamic deterioration in some patients with aortic valve endocarditis.
American Heart Journal, Sep 1, 1989
Recently, we have observed the echogenicity of turbulent intracardiac blood flow across a stenoti... more Recently, we have observed the echogenicity of turbulent intracardiac blood flow across a stenotic mitral valve. This prompted us to determine the frequency of this finding and to reexamine the accepted hypothesis that blood echogenicity is always the result of red cel aggregation
Stroke, 1992
Acute paraplegia must be investigated promptly to exclude reversible causes. In this report we il... more Acute paraplegia must be investigated promptly to exclude reversible causes. In this report we illustrate the usefulness of transesophageal echocardiography in identifying the vascular etiologies of acute paraplegia. Two patients presented with acute paraplegia, one spontaneously and the other after removal of an intra-aortic balloon pump catheter. Through the use of transesophageal echocardiography, we excluded aortic dissection and identified protruding atherosclerotic plaques in the descending thoracic aorta of each patient. Embolization of atheromatous material from the thoracic aorta was considered the most likely etiology of paraplegia in both cases. Embolization from atherosclerotic plaques in the thoracic aorta may be an underestimated cause of acute paraplegia. Transesophageal echocardiography provides a safe, rapid, and reliable tool for investigating a vascular etiology of acute paraplegia.
Daehanimsangchoeumpahakoeji, Nov 30, 2022
Background/Aims: Little is known about the complex anatomy of right ventricular (RV) torsion in t... more Background/Aims: Little is known about the complex anatomy of right ventricular (RV) torsion in the general population. This study was designed to assess RV's global and segmental torsional motion in subjects without cardiac pathologies. Methods: We used the Vivid 7 ultrasound system (GE Healthcare, Chicago, IL, USA) to acquire parasternal short-axis views of the RV at the basal and apical levels, and analyzed global and segmental torsion using a 2D speckle tracking algorithm in EchoPAC workstation (GE Healthcare, Wauwatosa, WI, USA). Results: Forty-eight individuals (44 ± 17 years, 54% male) were included, with either normal left ventricular diastolic function (group I, n = 40) or grade I diastolic dysfunction (group II, n = 8). Group I showed global peak systolic torsion of 9.0 ± 6.6 degrees with higher segmental torsion in the mid-interventricular septum (IVS) than in the anterior walls (p = 0.001). Global RV torsion showed a very strong positive correlation with apical rotation (r = 0.91, p < 0.001). Group I exhibited higher segmental torsion in the anterior-IVS and mid-IVS walls than group II (9.8 ± 7.1 vs. 3.5 ± 9.6 degrees, p = 0.036; 10.4 ± 9.1 vs. 2.4 ± 12.3 degrees, p = 0.038, respectively). Conclusions: Analysis of RV segmental torsion was feasible using a 2D speckle tracking algorithm. Apical rotation can be used as a simplified index of global RV torsion. Further studies are needed to evaluate the clinical impact of RV torsion in various pathologies.
European Heart Journal, Feb 11, 2020
Aims Right ventricular dysfunction (RVD) is an important determinant of functional status and sur... more Aims Right ventricular dysfunction (RVD) is an important determinant of functional status and survival in various diseases states. Data are sparse on the epidemiology and outcome of patients with severe RVD. This study examined the characteristics, aetiology, and survival of patients with severe RVD.
PURPOSE: Doppler ultrasound is a sensitive modality for detecting and quantitating valvular regur... more PURPOSE: Doppler ultrasound is a sensitive modality for detecting and quantitating valvular regurgitation in patients with infective endocarditis. Because valvular regurgitation leads to heart failure, we evaluated the prognostic significance of Doppler-detected valvular regurgitation in patients with endocarditis who had not yet developed clinical heart failure.
Heart Rhythm, May 1, 2005
The National Medical Journal of India, 2020
Percutaneous mitral valve repair is an accepted treatment of choice in Europe and North America f... more Percutaneous mitral valve repair is an accepted treatment of choice in Europe and North America for severe primary or secondary mitral regurgitation, in highly symptomatic patients for whom surgical repair is prohibitively high risk. We describe the first use of the MitraClip in India in a frail elderly female with symptomatic heart failure from severe primary mitral regurgitation who was considered high risk for surgical repair. She had substantial improvement in her symptoms as well as quality of life following the procedure.
Journal of Heart and Lung Transplantation, Apr 1, 2021
Background Myocardial fibrosis is an important contributor for development of diastolic dysfuncti... more Background Myocardial fibrosis is an important contributor for development of diastolic dysfunction. We investigated the impact of sirolimus as primary immunosuppression on diastolic dysfunction and fibrosis progression among heart transplantation recipients. Methods and Results In 100 heart transplantation recipients who were either treated with a calcineurin inhibitor (CNI) (n=51) or converted from CNI to sirolimus (n=49), diastolic function parameters were assessed using serial echocardiograms and right heart catheterizations. Myocardial fibrosis was quantified on serial myocardial biopsies. After 3 years, lateral e′ increased within the sirolimus group but decreased in the CNI group (0.02±0.04 versus −0.02±0.04 m/s delta change; P =0.003, respectively). Both pulmonary capillary wedge pressure and diastolic pulmonary artery pressure significantly decreased in the sirolimus group but remained unchanged in the CNI group (−1.50±2.59 versus 0.20±2.20 mm Hg/year; P =0.02; and −1.72±3.39 versus 0.82±2.59 mm Hg/year; P =0.005, respectively). A trend for increased percentage of fibrosis was seen in the sirolimus group (8.48±3.17 to 10.10±3.0%; P =0.07) as compared with marginally significant progression in the CNI group (8.76±3.87 to 10.56±4.34%; P =0.04). The percent change in fibrosis did not differ significantly between the groups (1.62±4.67 versus 1.80±5.31%, respectively; P =0.88). Conclusions Early conversion to sirolimus is associated with improvement in diastolic dysfunction and filling pressures as compared with CNI therapy. Whether this could be attributed to attenuation of myocardial fibrosis progression with sirolimus treatment warrants further investigation.
Journal of Heart and Lung Transplantation, Apr 1, 2012
Purpose: The total artificial heart (TAH) orthotopically replaces the cardiac ventricles, interru... more Purpose: The total artificial heart (TAH) orthotopically replaces the cardiac ventricles, interrupting neural and hormonal signaling pathways dependent upon the myocardium. We hypothesized that repletion of BNP after ventriculectomy would improve renal function and increase urine output. Methods and Materials: We measured urine output (UO), glomerular filtration rate (GFR) and various neurohormones after infusion of low-dose nesiritide (0.005 mcg/kg/min) in 5 patients during the first 48 hours after surgery. Patients had greater UO 48 hours after ventriculectomy compared to controls (126 Ϯ 26 mL/hr vs. 66 Ϯ 38 mL/hr, P ϭ 0.02). Results: Serum BNP concentrations decreased after ventriculectomy from 725 Ϯ 270 pg/mL to 48 Ϯ 26 pg/mL (P ϭ 0.006) and UO decreased from 124 Ϯ 54 mL/hr to 48 Ϯ 35 mL/hr (P ϭ 0.01). With nesiritide, UO increased to 163 Ϯ 113 ml/hr (P ϭ 0.04) without any change in GFR. Infusion of nesiritide was associated with suppression of aldosterone, without modulation of plasma renin activity. All patients were able to be gradually tapered off of nesiritide at 19 to 49 day after surgery. Conclusions: Infusion of low dose exogenous BNP increased UO implantation of a TAH. In contrast to patients with acute decompensated heart failure, the effects of BNP may be enhanced after ventriculectomy and possibly afford renal protection early after TAH implantation.
Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques, Oct 1, 1998
Stress echocardiography, both pharmacologic and physiological, is an established noninvasive diag... more Stress echocardiography, both pharmacologic and physiological, is an established noninvasive diagnostic method of detecting coronary artery disease. It also has a role in the assessment of patients with chest pain, the assessment of cardiovascular risk before noncardiac surgery, the assessment of patients after a myocardial infarction, the detection of viability in dysfunctional myocardium, and the prediction of functional recovery. The prognostic value of stress echocardiography is emerging. In this article, we discuss the methodology, diagnostic accuracy, and various clinical applications of stress echocardiography. We also review its limitations and compared it with other noninvasive methods of assessing patients with coronary artery disease.
Journal of Exercise, Sports & Orthopedics, 2015
Echo/Doppler screening should be looked upon as a strategy used in a select population of healthy... more Echo/Doppler screening should be looked upon as a strategy used in a select population of healthy, asymptomatic individuals to identify pre-emergent disease. Using focused echo/Doppler screening the incidence of a cardiovascular finding in athletes has been reported to be roughly one case in every 170 athletes screened with a "false positive" finding in only 8 of 508 athletes [2, 10, 13-15]. We describe how to provide a highest quality, exceptionally low cost pathophysiologic athletic screening test, which is validated to differentiate the status of a normal state from an abnormal life-threatening pathophysiologic state. Matching pre-emergent disease (without phenotypic expression) "associated" with sudden death through diastolic parameters is the key to differentiating normal from abnormal pathophysiology [5, 9, 16-24]. These data are focused on two principal objectives: detect an imminent life-threatening state at a time when the opportunity for prevention is optimal [25, 26], and define the magnitude of imminent risk that enlightens physician decision making and management [23, 26-28]. Rule-Out vs. Rule-in Screening A sensitive screening approach must be distinguished from a specific screening methodology [5, 6]. The current trend in athletic screening is searching for an "abnormal" disease feature in a low risk population. This fact alone (searching for a specific rare event) is a major contributor to the controversies and shortfalls surrounding athletic screening [5, 6]. The most optimal screening test for a large, asymptomatic athletic population prioritizes testing to confirm wellness and rule out disease. An abnormality in screening would be referred for comprehensive evaluation. The rule out principle is important because the penalty for missing a disease has the potential for athletic death. This principle reduces the number of specific diseases to be considered during screening. All cardiomyopathies are grouped as having abnormal diastolic tissue Doppler examination. Conversely, ruling in a disease is more applicable when confirming a high frequency disease. Confirming wellness
International Journal of Cardiology, 2021
Background: In patients with normal left ventricular ejection fraction, it may be difficult to di... more Background: In patients with normal left ventricular ejection fraction, it may be difficult to distinguish between the normal and diseased heart. Novel assessments of ventricular function, such as extracellular volume imaging, myocardial perfusion imaging and myocardial contraction fraction are emerging to better assess disease burden in these cases. This study endeavored to determine whether the ratio of myocardial volume in systole to myocardial volume in diastole (MVs/MVd), differs between normal hearts and those with disease states characterized by normal ejection fraction. Method: Consecutive patients from 2008 to 2018 with hypertrophic cardiomyopathy (HCM), cardiac amyloidosis, and heart failure with preserved ejection fraction (HFpEF) who underwent cardiac magnetic resonance imaging (MRI) were selected for inclusion, along with a sex-and age-matched cohort of normal volunteers who also underwent cardiac MRI. Manual tracings were performed on each MRI to calculate MVs/MVd, which was then compared across subgroups. Results: Included were 50 patients with HCM, 50 patients with cardiac amyloidosis, 26 patients with HFpEF, and 30 normal subjects. Age was 54.1 years (SD 16.7); mean MVs/MVd was 0.88 (SD 0.04) in the normal subgroup, 1.03 (SD 0.06) in HCM patients, 1.03 (SD 0.06) in cardiac amyloidosis patients, and 0.97 (SD 0.02) in HFpEF patients, with all pathology subgroups different from the normal subgroup (p < .0001 for each). The ratio of MVs/ MVd discriminated diseased from normal with c statistic 0.989 (p < .001). Conclusions: This study suggests that a novel and easily-captured metric of ventricular function, MVs/MVd, can differentiate normal ventricular function from multiple cardiomyopathies with normal ejection fractions.
Developments in Cardiovascular Medicine, 1989
Cardiovascular morbidity and mortality of cardiac surgery is often due to failure to recognize un... more Cardiovascular morbidity and mortality of cardiac surgery is often due to failure to recognize underlying myocardial ischemia intraoperatively [1–2]. Perioperative myocardial infarction is an important complication whose incidence varies from 5–23% [3] and has a direct bearing on subsequent cardiac morbidity [3–7]. Several techniques have been used in an attempt to diagnose perioperative and intraoperative myocardial injury [8–18]. However to date there is no in vivo method which reliably identifies ischemic myocardium.
Circulation, 2020
Introduction: Cardiovascular disease remains the leading cause of morbidity and mortality in pati... more Introduction: Cardiovascular disease remains the leading cause of morbidity and mortality in patients with amyloid light chain (AL) amyloidosis. Current prognostic evaluation in AL cardiomyopathy (AL-CM) largely relies upon disparate proxy measurements to assess mortality. With respect to observed myocardial volume changes between systole and diastole, we describe a single measurement derived from cardiac MRI (CMR) to assess mortality of AL-CM. Methods: A cohort of 129 consecutive patients with AL-CM undergoing CMR with amyloid protocol from the years 2001 - 1997 was reviewed. Myocardial volume change at end systole and end diastole was assessed by disc summation with CMR. The myocardial function index (MFI) was calculated by consolidating blood pool and myocardial volume measures as confluent components of myocardial function utilizing operator tracings. The association of MFI and death was assessed with adjusted hazard ratios (HR) derived by a Cox model. Results: Data at time of C...
European Journal of Cardio-Thoracic Surgery, 2021
This International Consensus Classification and Nomenclature for the congenital bicuspid aortic v... more This International Consensus Classification and Nomenclature for the congenital bicuspid aortic valve condition recognizes 3 types of bicuspid valves: 1. The fused type (right-left cusp fusion, right-non-coronary cusp fusion and left-non-coronary cusp fusion phenotypes); 2. The 2-sinus type (latero-lateral and antero-posterior phenotypes); and 3. The partial-fusion (forme fruste) type. The presence of raphe and the symmetry of the fused type phenotypes are critical aspects to describe. The International Consensus also recognizes 3 types of bicuspid valve-associated aortopathy: 1. The ascending phenotype; 2. The root phenotype; and 3. Extended phenotypes.
European Journal of Cardio-Thoracic Surgery, 2021
This International evidence-based nomenclature and classification consensus on the congenital bic... more This International evidence-based nomenclature and classification consensus on the congenital bicuspid aortic valve and its aortopathy recognizes 3 types of bicuspid aortic valve: 1. Fused type, with 3 phenotypes: right-left cusp fusion, right-non cusp fusion and left-non cusp fusion; 2. 2-sinus type with 2 phenotypes: Latero-lateral and antero-posterior; and 3. Partial-fusion or forme fruste. This consensus recognizes 3 bicuspid-aortopathy types: 1. Ascending phenotype; root phenotype; and 3. extended phenotypes.
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Papers by Krishnaswamy Chandrasekaran