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Featured researches published by Nirav J. Mehta.


American Heart Journal | 2003

Cardiac papillary fibroelastoma: a comprehensive analysis of 725 cases

Ramesh M. Gowda; Ijaz A. Khan; Chandra K. Nair; Nirav J. Mehta; Balendu C. Vasavada; Terrence J. Sacchi

BACKGROUND With the advent of echocardiography, cardiac papillary fibroelastoma (CPF) is being increasingly reported. The demographics, clinical characteristics, pathological features, treatment, and prognosis of CPF are examined. DATA COLLECTIONS Cases, case series and related articles on the subject in all languages were identified through a comprehensive literature search. RESULTS AND CONCLUSIONS Seven hundred twenty-five cases of CPF were identified. Males comprised 55% of patients. Highest prevalence was in the 8th decade of life. The valvular surface was the predominant locations of tumor. The most commonly involved valve was the aortic valve, followed by the mitral valve. The left ventricle was the predominant nonvalvular site involved. No clear risk factor for development of CPF has been reported. Size of the tumor varied from 2 mm to 70 mm. Clinically, CPFs have presented with transient ischemic attack, stroke, myocardial infarction, sudden death, heart failure, presyncope, syncope, pulmonary embolism, blindness, and peripheral embolism. Tumor mobility was the only independent predictor of CPF-related death or nonfatal embolization. Symptomatic patients should be treated surgically because the successful complete resection of CPF is curative and the long-term postoperative prognosis is excellent. The symptomatic patients who are not surgical candidates could be offered long-term oral anticoagulation, although no randomized controlled data are available on its efficacy. Asymptomatic patients could be treated surgically if the tumor is mobile, as the tumor mobility is the independent predictor of death or nonfatal embolization. Asymptomatic patients with nonmobile CPF could be followed-up closely with periodic clinical evaluation and echocardiography, and receive surgical intervention when symptoms develop or the tumor becomes mobile.


International Journal of Cardiology | 2003

Cardiac arrhythmias in pregnancy: clinical and therapeutic considerations

Ramesh M. Gowda; Ijaz A. Khan; Nirav J. Mehta; Balendu C. Vasavada; Terrence J. Sacchi

Pregnancy can precipitate cardiac arrhythmias not previously present in seemingly well individuals. Risk of arrhythmias is relatively higher during labor and delivery. Potential factors that can promote arrhythmias in pregnancy and during labor and delivery include the direct cardiac electrophysiological effects of hormones, changes in autonomic tone, hemodynamic perturbations, hypokalemia of pregnancy, and underlying heart disease. Paroxysmal supraventricular and ventricular tachycardia may cause hemodynamic compromise with consequences to the fetus. Management of arrhythmias in pregnant women is similar to that in non-pregnant but a special consideration must be given to avoid adverse fetal effects. No drug therapy is usually needed for the management of supraventricular or ventricular premature beats, but potential stimulants, such as smoking, caffeine, and alcohol should be eliminated. In paroxysmal supraventricular tachycardia, vagal stimulation maneuvers should be tried first. Adenosine or a cardioselective beta-blocker could be used if vagal maneuvers are ineffective. Alternatively, verapamil or diltiazem may be given. In pregnant women with atrial fibrillation, the goal of treatment is conversion to sinus rhythm or to control ventricular rate by a cardioselective beta-adrenergic blocker drug or digoxin. Ventricular arrhythmias may occur in the pregnant women with cardiomyopathy, congenital heart disease, valvular heart disease, or mitral valve prolapse. Termination of ventricular arrhythmias can usually be achieved by intravenous lidocaine or procainamide or by electrical cardioversion. Amiodarone is not safe for the fetus. Beta-blocker therapy must be continued during pregnancy and postpartum period in women with long QT syndrome and torsade de pointes.


American Heart Journal | 2003

Clinical usefulness and prognostic value of elevated cardiac troponin I levels in acute pulmonary embolism

Nirav J. Mehta; Ketan Jani; Ijaz A. Khan

BACKGROUND Right ventricular myocardial ischemia and injury contribute to right ventricular dysfunction and failure during acute pulmonary embolism. The objective of this study was to evaluate the clinical usefulness of cardiac troponin I (cTnI) in the assessment of right ventricular involvement and short-term prognosis in acute pulmonary embolism METHODS Thirty-eight patients with acute pulmonary embolism were included in the study. Clinical characteristics, right ventricular involvement, and clinical outcome were compared in patients with elevated levels of serum cTnI versus patients with normal levels of serum cTnI. RESULTS Among the study population (n = 38 patients), 18 patients (47%) had elevated cTnI levels (mean +/- SD 1.6 +/- 0.7 ng/mL, range 0.7-3.7 ng/mL, median, 1.4 ng/mL), and comprised the cTnI-positive group. In the other 20 patients, the serum cTnI levels were normal (< or =0.4 ng/mL), and they comprised the cTnI-negative group. In the cTnI-positive group (n = 18 patients), 12 patients (67%) had right ventricular dilatation/hypokinesia, compared with 3 patients (15%) in the cTnI-negative group (n = 20 patients, P =.004). Right ventricular systolic pressure was significantly higher in the cTnI-positive group (51 +/- 8 mm Hg vs 40 +/- 9 mm Hg, P =.002). Cardiogenic shock developed in a significantly higher number of patients with elevated serum cTnI levels (33% vs 5%, P =.01). In patients with elevated cTnI levels, the odds ratio for development of cardiogenic shock was 8.8 (95% CI 2.5-21). CONCLUSIONS Patients with acute pulmonary embolism with elevated serum cTnI levels are at a higher risk for the development of right ventricular dysfunction and cardiogenic shock. Serum cTnI has a role in risk stratification and short-term prognostication in patients with acute pulmonary embolism.


International Journal of Cardiology | 2003

Amiodarone for pharmacological cardioversion of recent-onset atrial fibrillation

Ijaz A. Khan; Nirav J. Mehta; Ramesh M. Gowda

The efficacy and safety of amiodarone for pharmacological cardioversion of recent-onset atrial fibrillation was examined by reviewing the trials on the subject identified through a comprehensive literature search. Amiodarone has been used both intravenously (i.v.) and orally for the pharmacological cardioversion of recent-onset atrial fibrillation. Intravenous amiodarone has been used as a bolus only or as a bolus followed by a continuous i.v. infusion until conversion or up to 24 h. The dose of i.v. bolus given ranged from 3 to 7 mg/kg body weight and that of infusion from 900 to 3000 mg/day. The efficacy reported is 34-69% with the bolus only regimens, and 55-95% with the bolus followed by infusion regimens. Only the higher dose (>1500 mg/day) amiodarone is superior to placebo in converting recent-onset atrial fibrillation to sinus rhythm. The highest 24-h conversion rates have been reported with the i.v. regimen of 125 mg/h until conversion or a maximum of 3 g and the oral regimen of 25-30 mg/kg body weight administered as a single loading-dose (>90% and >85%, respectively). Most of the conversions occur after 6-8 h of the initiation of therapy. Predictors of successful conversion are shorter duration of atrial fibrillation, smaller left atrial size, and higher amiodarone dose. Amiodarone is not superior to the other antiarrhythmic drugs conventionally used for the pharmacological cardioversion of recent-onset atrial fibrillation but is relatively safe in patients with structural heart disease and in those with depressed left ventricle function. Therefore, amiodarone could be used particularly in patients with structural heart disease and in those with left ventricular systolic dysfunction as the use of class IC drugs, propafenone and flecainide, for cardioversion of atrial fibrillation is contraindicated in such patients.


Journal of the American College of Cardiology | 2001

Prognostic value of serum cardiac troponin I in ambulatory patients with chronic renal failure undergoing long-term hemodialysis: A two-year outcome analysis

Ijaz A. Khan; Norrapol Wattanasuwan; Nirav J. Mehta; Aung Tun; Narpinder Singh; Harinder K. Singh; Balendu C. Vasavada; Terrence J. Sacchi

OBJECTIVES We sought to evaluate the prognostic value of cardiac troponin I (cTnI) in asymptomatic, ambulatory patients with chronic renal failure treated with long-term hemodialysis. BACKGROUND Smaller, short-term follow-up studies on this subject have given conflicting results. METHODS A total of 126 ambulatory patients with chronic renal failure treated with long-term hemodialysis were followed for two years for all-cause mortality, cardiac mortality, all-cause hospital admissions and cardiac hospital admissions. Serum cTnI was measured before dialysis at the time of study entry. RESULTS One hundred two patients had normal serum levels of cTnI (< or =0.03 ng/ml) and 24 patients had elevated levels (0.015 +/- 0.007 vs. 0.053 +/- 0.029 ng/ml, p < 0.0001). No significant difference in all-cause mortality (20 vs. 4 deaths), cardiac mortality (4 vs. 1 death), all-cause hospital admissions (1.74 +/- 1.72 vs. 1.25 +/- 1.19 admissions/patient) or cardiac admissions (0.52 +/- 0.89 vs. 0.33 +/- 0.76 admissions/patient) was present between the patients with normal cTnI levels and those with elevated cTnI levels. Serum cTnI was not significantly different between patients who died versus those who survived (0.022 +/- 0.019 vs. 0.022 +/- 0.021 ng/ml). Serum cTnI was not an independent predictor of all-cause mortality, cardiac mortality, all-cause admissions or cardiac admissions. Age (older) and serum albumin (lower) were independent predictors of all-cause mortality, whereas a history of myocardial infarction was an independent predictor of cardiac mortality. Serum sodium (lower) was an independent predictor of all-cause hospital admissions, whereas hypertension and previous myocardial infarction were independent predictors of cardiac admissions. The best predictors of the time to death were age (older) and serum sodium level (lower), irrespective of the serum cTnI levels. CONCLUSIONS Cardiac troponin I has a limited role in predicting mortality and hospital admissions in asymptomatic patients with chronic renal failure treated with long-term hemodialysis.


Angiology | 2002

Stenotrophomonas maltophilia endocarditis: a systematic review.

Ijaz A. Khan; Nirav J. Mehta

The disease characteristics, management, and outcome of Stenotrophomonas maltophilia endocarditis were evaluated by examining the reports on the subject identified through a comprehensive literature search. Twenty-three (17 male) cases of S. maltophilia endocarditis were identified. Mean age was 41 ± 15 years. All patients presented with fever. Prosthetic valves were involved in 12 (52%) cases. Among native valves, the aortic valve was most frequently involved (50%), followed by the tricuspid valve (36%). Twenty (87%) patients had underlying risk factors for the development of endocarditis, including prior valvular or congen ital heart disease surgery (60%), intravenous drug abuse (32%), and infected intravascular lines (18%). The endocarditis was postoperative in 14 patients. Seventeen (74%) patients experienced complications including septic embolism (23%), cardiac abscesses (23%), and congestive heart failure ( 18%). A combination of two or more antibiotics was used in all cases except one. The frequently used antibiotics were aminoglycosides (59%), trimethoprim sulfamethoxazole (48%), and penicillins (48%). One half of the patients required cardiac surgery, but the proportion of surgically treated cases was higher among prosthetic valve endocarditis (62%). Mortality was 39% and was equally distributed between patients with prosthetic and native valve endocarditis. The S. maltophilia endocarditis carries high compli cation and mortality rates. The antibiotic regimen should consist of a combination of multiple antibiotics guided by the sensitivity panel. Early surgery may be considered in patients not responding to antibiotic treatment and in those with prosthetic valve endocarditis.


Angiology | 2003

HIV-associated coronary artery disease.

Nirav J. Mehta; Ijaz A. Khan

Cases, case series, and related articles on coronary artery disease in patients with human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome (AIDS) iden tified through a comprehensive literature search were examined for clinical characteristics and angiographic findings of HIV-associated coronary artery disease. Among 129 identified cases, 91 % were males. The mean age was 42.3 ± 10.2 (SD) years (range, 23 to 77 years). The interval between the diagnosis of HIV infection and the diagnosis of coronary artery disease was 72 ±60 (SD) months. Degree of immunosuppression was variable (CD4 mean, 313 ±209 cells/mm3; range, 6-1070 cells/mm 3). There was no correlation between the CD4 cell count and the development and progression of coronary artery disease. Similarly, the development and progression of coronary artery disease was independent of the presence of HIV-related opportunistic infections. Acute myocardial infarction was the initial presentation in 77% of patients. In 76 patients, information on diseased vessels was available: 36 (47%) patients had 3-vessel disease, 14 (18%) patients had 2-vessel disease, and 26 patients (35%) had 1-vessel disease. The left anterior descending artery was involved in 47 (62%) patients while the left circumflex and right coronary arteries were involved in 34 (45%) and 38 (50%) patients, respectively. Thirty-two (25%) patients underwent catheter-based or surgical revascularization. Data were not adequate to assess the prognosis following the acute coronary events or revas cularization. The histologic characteristics unique to HIV-associated coronary arteriopathy were diffuse circumferential involvement of the vessel with an unusual proliferation of smooth muscle cells, mixed with abundant elastic fibers, resulting in endoluminal protrusions. Coronary artery disease was a late complication of AIDS.


Angiology | 2004

Right atrial extension of primary venous leiomyosarcoma: pulmonary embolism and Budd-Chiari syndrome at presentation-a case report.

Ramesh M. Gowda; Mamatha R. Gowda; Nirav J. Mehta; Rhonda Osborne; Ronda Bixon; Balendu C. Vasavada; Terrence J. Sacchi

Venous leiomyosarcomas are rare and arise predominantly in the inferior vena cava (IVC). The clinical findings are nonspecific and may precede the diagnosis by several years. IVC leiomyosarcoma is predominantly seen in women. Intracavitary extension of vascular tumors tends to result from embolization or propagation along great veins, and this is a serious risk factor for pulmonary embolism and sudden death when it reaches the right heart. Modern imaging modalities using computed tomography, magnetic resonance imaging, individually or in combination with cavography, ultrasound, and echocardiography, allow an early and accurate preoperative diagnosis, resulting in a higher rate of surgical resection and improved survival. The authors present a 72-year-old woman who presented with pulmonary embolism and Budd-Chiari syndrome. Pathological examination revealed a leiomyosarcoma. The tumor, involving the IVC, was diagnosed with imaging techniques that showed intracardiac extension of a primary venous leiomyosarcoma. The literature discussing leiomyosarcoma of the IVC is briefly reviewed.


Angiology | 2001

Peripartum cardiomyopathy: Clinical and therapeutic aspects

Nirav J. Mehta; Rajal N. Mehta; Ijaz A. Khan

Peripartum cardiomyopathy is an under-recognized form of dilated cardiomyopathy of unknown cause and is associated with excess morbidity and mortality in women of childbearing age. Incidence of peripartum cardiomyopathy ranges from 1 in 1,300 to 1 in 15,000 pregnancies. The diagnostic criteria are onset of heart failure in the last month of pregnancy or in first 5 months postpartum, absence of determinable cause for cardiac failure, and absence of a demonstrable heart disease before the last month of pregnancy. Multiparity, twin births, advanced maternal age, preeclampsia, gestational hypertension, and black race are known risk factors. The exact cause of peripartum cardiomyopathy is unclear. The clinical presentation of patients with peri partum cardiomyopathy is similar to that of patients with systolic congestive heart failure. Little is known about the therapy of this disease, and the medical treatment is limited to the use of drugs for symptomatic control. Prospective, randomized, double-blind studies are needed to define the role of immunosuppressive treatment and to evaluate the role of conventional treatment of dilated cardiomyopathy in reducing the mortality rate of peripartum cardiomy opathy. About half the patients of peripartum cardiomyopathy recover without any complica tions. The prognosis is poor in patients with persistent cardiomyopathy. Persistence of disease after 6 months indicates irreversible cardiomyopathy and portends worse survival. The risk of developing peripartum cardiomyopathy in subsequent pregnancies remains high. The clinical and therapeutic aspects of the peripartum cardiomyopathy are discussed.


Angiology | 2003

Cardiac Tamponade in Patients with Human Immunodeficiency Virus Disease

Ramesh M. Gowda; Ijaz A. Khan; Nirav J. Mehta; Mamatha R. Gowda; Terrence J. Sacchi; Balendu C. Vasavada

The characteristics of cardiac tamponade in patients with human immunodeficiency virus (HIV) disease were examined by evaluating the cases, case series, and related articles, including autopsy series, identified through a comprehensive literature search. One-hundred eighty-five cases of cardiac tamponade have been reported in patients with HIV disease. Sex data were available in 176 patients, of whom 154 (87%) were males. The mean age was 34.7 ±10.4 years (range, 11 months to 61 years). Mean CD4 cell count was 98 ±95 cells/mm3 (range, 3 to 430 cells/mm3). The most common etiology of pericardial tamponade was mycobacterial infection (78 patients), including Mycobacterium tuberculosis, Mycobacterium avium-intracellulare, and Mycobacterium kansasii. A bacterial cause was found in 20 patients (11%). Staphylococcus aureus was the predominant bacteria, followed by streptococci, Pseudomonas aeruginosa, Listeria monocytogenes, Klebsiella pneumoniae, and Rhodococcus equi. Lymphoma was found in 15 (8%) patients and Kaposi sarcoma in 13 (7%) patients. Numerous unusual organisms, including Cryptococcus neoformans, Nocardia asteroides, Aspergillus species, cytomegalo virus, and herpes simplex were also associated with cardiac tamponade in HIV patients. Occasionally, HIV itself was involved in the pathogenesis. In 48 patients (26%), no cause was found or reported. The most common clinical presentation was dyspnea, followed by fever, cough, chest pain, and cardiac arrest. The predominant pericardial fluid color composition was serosanguineous. The majority of patients died during hospitalization or in the immediate follow-up period. Vigilance for cardiac tamponade in patients with HIV disease, especially in those with opportunistic infections and/or malignancies, and cardiac symptoms, may result in early and proper management of cardiac tamponade in these patients.

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Terrence J. Sacchi

New York Methodist Hospital

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Ramesh M. Gowda

Beth Israel Medical Center

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Ketan Jani

State University of New York System

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