Amitoj Singh

The role of implantable cardioverter-defibrillators in patients with continuous flow left ventricular assist devices — A meta-analysis

BACKGROUND Left ventricular assist devices (LVADs) and implantable cardioverter defibrillators (ICD) are each known to improve mortality in patients with advanced congestive heart failure (CHF). If ICDs contribute to improved survival specifically in recipients of LVADs is currently unknown. AIM To evaluate the impact of presence of ICD on mortality in continuous flow LVAD recipients. METHODS A meta- analysis of available literature was performed. PubMed, Embase and Google Scholar databases were searched for studies that compared mortality in continuous flow LVAD patients with ICDs (new implantation or no de-activation) and without ICDs (including de-activation of existing implant). Pooled analysis using a fixed effects model was used for outcomes of interest. RESULTS We included 3 observational studies for a total of 292 patients (203 (69.5%) with ICD versus 89 (30.5%) without ICD). The presence of an active ICD was not associated with improved survival [OR 0.63, 95% CI 0.33-1.18; p=0.15]. In bridge to transplantation [BT] patients (224 patients, 149 with ICD versus 75 without ICD), an active ICD was not associated with a higher probability of survivzal [OR 1.47, 95% CI 0.78-2.76; p=0.23]. There was no difference in the occurrence of severe right ventricular dysfunction or failure between two groups [OR 0.78, 95% CI 0.42-1.47; p=0.45]. The risk of LVAD related complications were similar [OR 0.68, 95% CI 0.35-1.31; P=0.25]. CONCLUSION This meta-analysis demonstrates that there is no survival benefit with ICD in heart failure patients supported with continuous flow LVAD. There is an urgent need of large-scale randomized trials to specifically address this issue.

Thirty-Day Readmissions After Left Ventricular Assist Device Implantation in the United States: Insights From the Nationwide Readmissions Database

Background: Early readmissions contribute significantly to heart failure–related morbidity and negatively affect quality of life. Data on left ventricular assist device (LVAD)–related 30-day readmissions are scarce and limited to small studies. Methods and Results: Patients undergoing LVAD implantation between January 2013 and November 2014 who survived the index hospitalization were identified in the Nationwide Readmissions Database. We analyzed the incidence, predictors, causes, and costs of 30-day readmissions. Of 2510 LVAD recipients, 788 (31%) were readmitted within 30 days. Length of index hospitalization ≥31 days (hazard ratio [HR], 1.26; 95% confidence interval [CI], 1.07–1.50) and female sex (HR, 1.19; 95% CI, 1.01–1.42) were associated with a higher risk of 30-day readmission, whereas private insurance (HR, 0.83; 95% CI, 0.70–0.99), pre-LVAD use of short-term mechanical circulatory support (HR, 0.53; 95% CI, 0.29–0.98), and discharge to a short-term hospital facility (HR, 0.41; CI, 0.21–0.78) were associated with a lower risk. Cardiac causes accounted for 23.8% of readmissions: heart failure (13.4%) and arrhythmias (8.1%). Noncardiovascular causes accounted for 76.2% of readmissions: infection (30.2%), bleeding (17.6%), and device-related causes (8.2%). Mean length of stay for readmission was 10.7 days (median, 6 days), and average hospital cost per readmission was

Live/Real Time Three-Dimensional Transesophageal Echocardiographic Findings in Caseous Mitral Annular Calcification

34 948±2457. Conclusions: Early readmissions are frequent after LVAD implantation even in contemporary times. Preimplant identification of high-risk patients, and a protocol-driven follow-up using a multidisciplinary approach will be needed to reduce readmissions and improve outcomes.

Cardiac molecular imaging to track left ventricular remodeling in heart failure.

We describe a 77‐year‐old female with hypertrophic cardiomyopathy in whom live/real time three‐dimensional transesophageal echocardiography (3DTEE) provided incremental value over two‐dimensional transthoracic and transesophageal echocardiography (2DTTE, 2DTEE) and three‐dimensional transthoracic echocardiography (3DTTE) in making a more comprehensive assessment and a more confident diagnosis of caseous mitral annular calcification. 3DTEE revealed a portion of the mass to consist of small, multiple, highly echogenic discrete band‐like and punctate areas within a relatively much less echogenic stroma and surrounded by a well defined highly echogenic border. This appearance correlated with the pathological findings of calcific granules/strands located in a liquefied or semiliquefied interior providing a typical toothpaste like appearance. The highly echogenic outer border represented the residual outer portion or rim of the calcific mass which did not undergo liquefaction. These findings on 3DTEE which correlated with the toothpaste like appearance seen at surgery were not visualized on 2DTTE, 2DTEE, and 3DTTE. (Echocardiography 2010;27:1147‐1150)

Trends and Outcomes of Infective Endocarditis in Patients on Dialysis.

Cardiac left ventricular (LV) remodeling is the final common pathway of most primary cardiovascular diseases that manifest clinically as heart failure (HF). The more advanced the systolic HF and LV dysfunction, the worse the prognosis. The knowledge of the molecular, cellular, and neurohormonal mechanisms that lead to myocardial dysfunction and symptomatic HF has expanded rapidly and has allowed sophisticated approaches to understanding and management of the disease. New therapeutic targets for pharmacologic intervention in HF have also been identified through discovery of novel cellular and molecular components of membrane-bound receptor-mediated intracellular signal transduction cascades. Despite all advances, however, the prognosis of systolic HF has remained poor in general. This is, at least in part, related to the (1) relatively late institution of treatment due to reliance on gross functional and structural abnormalities that define the “heart failure phenotype” clinically; (2) remarkable genetic-based interindividual variations in the contribution of each of the many molecular components of cardiac remodeling; and (3) inability to monitor the activity of individual pathways to cardiac remodeling in order to estimate the potential benefits of pharmacologic agents, monitor the need for dose titration, and minimize side effects. Imaging of the recognized ultrastructural components of cardiac remodeling can allow redefinition of heart failure based on its “molecular phenotype,” and provide a guide to implementation of “personalized” and “evidence-based” evaluation, treatment, and longitudinal monitoring of the disease beyond what is currently available through randomized controlled clinical trials.

Cardiovascular Complications of Marijuana and Related Substances: A Review

Dialysis patients are at high risk for infective endocarditis (IE); however, no large contemporary data exist on this issue. We examined outcomes of 44 816 patients with IE on dialysis and 202 547 patients with IE not on dialysis from the Nationwide Inpatient Sample database from 2006 thorough 2011. Dialysis patients were younger (59 ± 15 years vs 62 ± 18 years) and more likely to be female (47% vs 40%) and African‐American (47% vs 40%; all P < 0.001). Hospitalizations for IE in the dialysis group increased from 175 to 222 per 10 000 patients (P trend = 0.04). Staphylococcus aureus was the most common microorganism isolated in both dialysis (61%) and nondialysis (45%) groups. IE due to S aureus (adjusted odds ratio [aOR]: 1.79, 95% confidence interval [CI]: 1.73‐1.84), non‐aureus staphylococcus (aOR: 1.72, 95% CI: 1.64‐1.80), and fungi (aOR: 1.4, 95% CI: 1.12‐1.78) were more likely in the dialysis group, whereas infection due to gram‐negative bacteria (aOR: 0.85, 95% CI: 0.81‐0.89), streptococci (aOR: 0.38, 95% CI: 0.36‐0.39), and enterococci (aOR: 0.78, 95% CI: 0.74‐0.82) were less likely (all P < 0.001). Dialysis patients had higher in‐hospital mortality (aOR: 2.13, 95% CI: 2.04‐2.21), lower likelihood of valve‐replacement surgery (aOR: 0.82, 95% CI: 0.76‐0.86), and higher incidence of stroke (aOR: 1.08, 95% CI: 1.03‐1.12; all P < 0.001). We demonstrate rising incidence of IE‐related hospitalizations in dialysis patients, highlight significant differences in baseline comorbidities and microbiology of IE compared with the general population, and validate the association of long‐term dialysis with worse in‐hospital outcomes.

Pheochromocytoma and stress cardiomyopathy: Insight into pathogenesis

The recreational use of cannabis has sharply increased in recent years in parallel with its legalization and decriminalization in several countries. Commonly, the traditional cannabis has been replaced by potent synthetic cannabinoids and cannabimimetics in various forms. Despite overwhelming public perception of the safety of these substances, an increasing number of serious cardiovascular adverse events have been reported in temporal relation to recreational cannabis use. These have included sudden cardiac death, vascular (coronary, cerebral and peripheral) events, arrhythmias and stress cardiomyopathy among others. Many of the victims of these events are relatively young men with few if any cardiovascular risk factors. However, there are reasons to believe that older individuals and those with risk factors for or established cardiovascular disease are at even higher danger of such events following exposure to cannabis. The pathophysiological basis of these events is not fully understood and likely encompasses a complex interaction between the active ingredients (particularly the major cannabinoid, Δ9-tetrahydrocannabinol), and the endo-cannabinoid system, autonomic nervous system, as well as other receptor and non-receptor mediated pathways. Other complicating factors include opposing physiologic effects of other cannabinoids (predominantly cannabidiol), presence of regulatory proteins that act as metabolizing enzymes, binding molecules, or ligands, as well as functional polymorphisms of target receptors. Tolerance to the effects of cannabis may also develop on repeated exposures at least in part due to receptor downregulation or desensitization. Moreover, effects of cannabis may be enhanced or altered by concomitant use of other illicit drugs or medications used for treatment of established cardiovascular diseases. Regardless of these considerations, it is expected that the current cannabis epidemic would add significantly to the universal burden of cardiovascular diseases.

CHILDBIRTH RELATED COMPLICATIONS IN WOMEN WITH HYPERTROPHIC CARDIOMYOPATHY

AIM To investigate the occurrence of cardiomyopathy (CMP) in a cohort of patients with histologically proven pheochromocytoma (pheo), and to determine if catecholamine excess was causative of the left ventricular (LV) dysfunction. METHODS A retrospective chart review spanning years 1998 through 2014 was undertaken and patients with a diagnosis of pheo confirmed with histopathologic examination were included. Presenting electrocardiograms and cardiac imaging studies were reviewed. Transthoracic echocardiography (TTE), ventriculography or single positron emission computed tomography imaging was evaluated and if significant abnormalities [left ventricular hypertrophy (LVH) or LV dysfunction] were noted in the pre operative period a follow up post-operative study was also analyzed. Multivariate analysis using logistic regression was used to investigate independent predictors for outcomes of interest, LV dysfunction and LVH. RESULTS We identified 18 patients with diagnosis of pheo confirmed on pathology. Mean age was 54.3 ± 19.3 years and 11 (61.1%) patients were females. 50% of such patients had either resistant hypertension or labile blood pressures during hospitalization, which had raised suspicion for a pheo. Cardiac imaging studies were available for 12 (66.7%) patients at the time of inclusion into study and preceding the adrenalectomy. 7 (58.3%) patients with a TTE available for review had mild or more severe LVH while 3 (25%) patients had LV dysfunction of presumably acute onset. In a multivariate analysis, elevated catecholamine levels as assessed by urinary excretion of metabolites was not an independent predictor of development of LV systolic dysfunction or of presence of LVH on TTE. Two female patients with a preceding history of hypertension had marked LV hypertrophy and systolic anterior motion of the mitral valve. Prolongation of the QTc interval was noted in 5 (27.8%) patients but no acute arrhythmias were observed in any patient. CONCLUSION This study adds to the growing body of literature on the predilection of patients with pheochromocytomas to develop non-ischemic CMP. Degree of catecholamine excess as measured by urinary secretion of metabolites did not predict the development of CMP but 2 of 3 patients developed CMP in the setting of significant acute physiologic stress. Our findings provide support to the proposed etiologic role of elevated catecholamines in TC and other stress induced forms of CMP, however, activation of a brain-neural-cardiac axis from acute stress and local release of catecholamines but not chronic catecholamine elevations are likely to be responsible in pheo related CMP.

CARDIOVASCULAR COMPLICATIONS AND IN-HOSPITAL OUTCOMES OF CHAGAS’ DISEASE IN THE UNITED STATES FROM 2003-2011

Background: Childbirth poses increased risk of death and adverse cardiovascular outcomes in women with hypertrophic cardiomyopathy (HCM). Data is, however, scarce and limited to small number of patients reported from large tertiary care centers. We aimed to examine the maternal cardiovascular and

Posttraumatic stress disorder after myocardial infarction and coronary artery bypass grafting

Background: Chagas’ disease (CD), caused by Trypanosoma cruzi, has been increasingly diagnosed as a cause of cardiovascular disease in the US. We aimed to examine trends of hospital admissions and cardiovascular outcomes of CD. Methods: Search of 2003-2011 Nationwide Inpatient Sample database