Kenneth Silverman

Bio: Kenneth Silverman is an academic researcher from Harvard University. The author has contributed to research in topics: Coronary artery disease & Cardiac catheterization. The author has an hindex of 16, co-authored 28 publications receiving 1646 citations. Previous affiliations of Kenneth Silverman include Beth Israel Deaconess Medical Center & Smithsonian Institution.

Cardiac sarcoid: a clinicopathologic study of 84 unselected patients with systemic sarcoidosis.

Abstract: Although sarcoid may involve the myocardium, there is little information on its incidence or significance. We studied 84 consecutive autopsied patients with sarcoidosis. The patients ranged in age from 18--80 years (average 46 years) and 61% were women; 23 (27%) of them had myocardial granulomas. In eight (35%) these were clinically silent, and in 15 (65%) there was a history of heart failure and/or arrhythmias and conduction defects. Of the 23 patients, only four (17%) had grossly evident, widespread myocardial lesions: three of these four (75%) had documented arrhythmias. All four had sudden, unexpected death at an average age of 36 years; in only two had sarcoid been suspected during life. The other 19 patients (83%) had microscopically evident granulomatous involvement. Of these, eight (42%) had a thythm or conduction disturbance and three (16%) sudden death, although none of those who suffered sudden death had a recognized rhythm or conduction disturbance. Nine (15%) of those without cardiac sarcoidosis had a rhythm or conduction disturbance and eight (13%) suffered a sudden death. The results show that although myocardial involvement occurs in at least 25% of patients with sarcoid, it most often involves a small portion of myocardium and is clinically silent. Since some of the 61 patients in whom myocardial lesions were not identified may still have had small microscopic granulomas, the true incidence of myocardial sarcoid may be even greater than suggested here. Rhythm and conduction disturbances are more common in the cardiac sarcoid group, but the findings suggest that only the small subset of patients with severe, grossly evident myocardial sarcoid are at increased risk for sudden death.

Myocardial salvage after intracoronary thrombolysis with streptokinase in acute myocardial infarction.

Abstract: Nine patients with acute myocardial infarction had cardiac catheterization and intracoronary infusions of streptokinase 2.3 to 4.3 hours (mean, 3.5) after the onset of symptoms. Occluded coronary arteries were opened within approximately 20 minutes in all patients, but reocclusion occurred in one patient. The immediate effect of thrombolysis on myocardial salvage was assessed with the intracoronary injection of thallium-201. Improved regional perfusion, indicating myocardial salvage after recanalization, was observed in seven of the nine patients. One patient, who had also sustained a nontransmural infarction one week before, had no change after thrombolysis. In the ninth patient, recanalization of a coronary artery was followed by reocclusion and worsening of the myocardial-perfusion defect. Intracoronary thallium-201 studies two weeks and three months after streptokinase infusion in two patients were unchanged in comparison with scintiscans performed 1.5 hours after thrombolysis. These short-term observations suggest that recanalization of obstructed coronary arteries after intracoronary thrombolysis can salvage jeopardized myocardium, However, evaluation of the long-term effects of this procedure on survival and myocardial function will require controlled clinical trials.

The pacing stress test: a reexamination of the relation between coronary artery disease and pacing-induced electrocardiographic changes.

Abstract: Electrocardiographic (ECG) changes during graded pacing-induced tachycardia have been considered unreliable as a test for the presence of coronary artery disease (CAD) because of poor sensitivity and specificity. As a result, atrial pacing has not been widely used as an alternative to exercise testing. However, the limited value of the pacing stress test may be related to technical aspects, such as the duration of pacing and ECG monitoring. To study this problem, 22 patients undergoing coronary cineangiography underwent standard exercise stress testing and graded tachycardia induced by atrial pacing. A 12-lead ECG recorder was used for both tests. Pacing tachycardia was terminated when 85% of maximal predicted heart rate had been achieved or when significant ischemic chest pain accompanied by diagnostic ECG changes occurred. The ECG was considered positive if at least 1 mm of horizontal or downsloping ST-segment depression was present. Six patients with normal or minimally diseased coronary arteries were compared to 16 patients with significant CAD. Of the patients without significant CAD, 5 (83%) had a negative electrocardiogram during both exercise and pacing. Of 16 patients with CAD, the electrocardiogram was positive for ischemia in 10 patients (63%) during exercise, in 15 (94%) during atrial pacing and in 12 (80%) after pacing. When the presence or absence of ECG changes was compared between the exercise and the pacing tests, there was a concordance of 90% (Fisher p less than 0.0015). Two patients without significant CAD (33%) had chest pain during both exercise and pacing. Among patients with CAD, 7 (44%) had chest pain during exercise and 8 (50%) had chest pain during atrial pacing.(ABSTRACT TRUNCATED AT 250 WORDS)

The stunned myocardium: prolonged, postischemic ventricular dysfunction.

Abstract: Myocardial ischemia has, for many decades, been viewed as an all-or-none process that causes myocardial necrosis when prolonged and severe, but whose effects are transient when it is brief or mild. In view of the evidence that the ischemic process may "hit, run and stun," perhaps our thinking about the consequences of myocardial ischemia should be expanded. According to this formulation, an ischemic insult not of sufficient severity of duration to produce myocardial necrosis may acutely affect myocardial repolarization and cause angina (hit); but these changes wane rapidly (run), when the balance between myocardial oxygen supply and demand has been reestablished. However, the ischemia may interfere with normal myocardial function, biochemical processes and ultrastructure for prolonged periods (stun). The severity and duration of these postischemic changes depend on the length and intensity of the ischemia, as well as on the condition of the myocardium at the onset of the ischemic episode. Furthermore, it is likely that when the myocardium is repeatedly stunned, it may exhibit chronic postischemic left ventricular dysfunction, an ill-defined condition. If prolonged, chronic postischemic left ventricular dysfunction can progress to myocardial scarring and ischemic cardiomyopathy, it may be important to determine how often it can be ameliorated by permanent improvement of myocardial perfusion by surgical treatment.

Sarcoidosis

Abstract: 结节病易误诊,据王洪武等~([1])收集国内18篇关于此病误诊的文献,误诊率高达63.2%,当然有误诊就会有误治,如孙永昌等~([2])报道26例结节病在影像学检查诊断的第一印象中拟诊结核5例,其中就有2例完成规范的抗结核治疗,为此应引起临床对本病诊治的重视。

The role of endomyocardial biopsy in the management of cardiovascular disease: A Scientific Statement from the American Heart Association, the American College of Cardiology, and the European Society of Cardiology Endorsed by the Heart Failure Society of America and the Heart Failure Association of the European Society of Cardiology

Abstract: The role of endomyocardial biopsy (EMB) in the diagnosis and treatment of adult and pediatric cardiovascular disease remains controversial, and the practice varies widely even among cardiovascular centers of excellence. A need for EMB exists because specific myocardial disorders that have unique prognoses and treatment are seldom diagnosed by noninvasive testing.1 Informed clinical decision making that weighs the risks of EMB against the incremental diagnostic, prognostic, and therapeutic value of the procedure is especially challenging for nonspecialists because the relevant published literature is usually cited according to specific cardiac diseases, which are only diagnosed after EMB. To define the current role of EMB in the management of cardiovascular disease, a multidisciplinary group of experts in cardiomyopathies and cardiovascular pathology was convened by the American Heart Association (AHA), the American College of Cardiology (ACC), and the European Society of Cardiology (ESC). The present Writing Group was charged with reviewing the published literature on the role of EMB in cardiovascular diseases, summarizing this information, and making useful recommendations for clinical practice with classifications of recommendations and levels of evidence. The Writing Group identified 14 clinical scenarios in which the incremental diagnostic, prognostic, and therapeutic value of EMB could be estimated and compared with the procedural risks. The recommendations contained in the present joint Scientific Statement are derived from a comprehensive review of the published literature on specific cardiomyopathies, arrhythmias, and cardiac tumors and are categorized according to presenting clinical syndrome rather than pathologically confirmed disease. The ultimate intent of this document is to provide an understanding of the range of acceptable approaches for the use of EMB while recognizing that individual patient care decisions depend on factors not well reflected in the published literature, such as local availability of specialized facilities, cardiovascular pathology expertise, and operator experience. The use of EMB …

The role of endomyocardial biopsy in the management of cardiovascular disease: a scientific statement from the American Heart Association, the American College of Cardiology, and the European Society of Cardiology.

Abstract: The role of endomyocardial biopsy (EMB) in the diagnosis and treatment of adult and pediatric cardiovascular disease remains controversial, and the practice varies widely even among cardiovascular centers of excellence. A need for EMB exists because specific myocardial disorders that have unique prognoses and treatment are seldom diagnosed by noninvasive testing.1 Informed clinical decision making that weighs the risks of EMB against the incremental diagnostic, prognostic, and therapeutic value of the procedure is especially challenging for nonspecialists because the relevant published literature is usually cited according to specific cardiac diseases, which are only diagnosed after EMB. To define the current role of EMB in the management of cardiovascular disease, a multidisciplinary group of experts in cardiomyopathies and cardiovascular pathology was convened by the American Heart Association (AHA), the American College of Cardiology (ACC), and the European Society of Cardiology (ESC). The present Writing Group was charged with reviewing the published literature on the role of EMB in cardiovascular diseases, summarizing this information, and making useful recommendations for clinical practice with classifications of recommendations and levels of evidence. The Writing Group identified 14 clinical scenarios in which the incremental diagnostic, prognostic, and therapeutic value of EMB could be estimated and compared with the procedural risks. The recommendations contained in the present joint Scientific Statement are derived from a comprehensive review of the published literature on specific cardiomyopathies, arrhythmias, and cardiac tumors and are categorized according to presenting clinical syndrome rather than pathologically confirmed disease. The ultimate intent of this document is to provide an understanding of the range of acceptable approaches for the use of EMB while recognizing that individual patient care decisions depend on factors not well reflected in the published literature, such as local availability of specialized facilities, cardiovascular pathology expertise, and operator experience. The use of EMB …

Assessment of systolic and diastolic ventricular properties via pressure-volume analysis: a guide for clinical, translational, and basic researchers.

Abstract: Assessment of left ventricular systolic and diastolic pump properties is fundamental to advancing the understanding of cardiovascular pathophysiology and therapeutics, especially for heart failure. The use of end-systolic and end-diastolic pressure-volume relationships derived from measurements of instantaneous left ventricular pressure-volume loops emerged in the 1970s as a comprehensive approach for this purpose. As invasive and noninvasive techniques for measuring ventricular volume improved over the past decades, these relations have become commonly used by basic, translational, and clinical researchers. This review summarizes 1) the basic concepts underlying pressure-volume analysis of ventricular and myocardial systolic and diastolic properties, 2) deviations from ideal conditions typically encountered in real-life applications, 3) how these relationships are appropriately analyzed, including statistical analyses, and 4) the most common problems encountered by investigators and the appropriate remedies. The goal is to provide practical information and simple guidelines for accurate application and interpretation of pressure-volume data as they pertain to characterization of ventricular and myocardial properties in health and disease.