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Marc Silver

Publications and source records attributed to Marc Silver.

8 recordsLinked to original sources
PubMed2006

Thrombotic "ghosts": echocardiographic appearance of thrombi with hollow cores and implications regarding mechanism of spontaneous clot lysis.

We present a case of a patient whose transesophageal echocardiogram revealed multiple thrombi in different stages of central lysis. This produced the appearance of undulating thin outer shells and lucent central cores resembling "ghosts." Although most thrombi appear to resolve by a lytic process that produces reduction in size from the exterior surface inward, the thrombi illustrated in this case appear to lyse from the interior outward. In this report we discuss the mechanisms of intracardiac clot lysis and speculate that a newly described protein factor, thrombin-mediated inhibition of fibrinolysis, may play a role in formation of hollow thrombi.

Aged↗
PubMed2004

Predictors of stroke in patients paced for sick sinus syndrome.

OBJECTIVES: This study was an analysis of factors associated with stroke in a population of patients paced for sinus node dysfunction in a large prospective clinical trial (Mode Selection Trial [MOST]). BACKGROUND: The effects of dual-chamber versus single-chamber ventricular pacing on subsequent stroke in patients with sinus node dysfunction are not known. METHODS: A total of 2,010 patients with sinus node dysfunction were randomized to ventricular or dual-chamber pacing and followed for a median of 33.1 months. RESULTS: The median participant age was 74 years. During 5,664 patient-years of follow-up, 90 strokes (11 hemorrhagic) occurred. By life-table analysis, the rate of stroke was 2.2% (95% confidence interval [CI] 1.6 to 2.9) at one year and 5.8% (95% CI 4.5 to 7.1) at four years. The incidence of stroke was not significantly different in dual-chamber (4%) as compared with ventricular-paced patients (4.9%) (hazard ratio [HR] 0.82, 95% CI 0.54 to 1.25, p = 0.36). Multivariable analysis demonstrated that significant predictors of stroke included prior stroke or transient ischemic attack, Caucasian race, hypertension, prior systemic embolism, and New York Heart Association functional class III or IV (p < 0.05); pacing mode remained non-significant after adjustment for these factors (p = 0.37). Clinically reported atrial fibrillation after implantation was a risk factor for stroke in this cohort after adjustment for other predictors of stroke (p = 0.042, HR 1.68 [95% CI 1.02 to 2.76]). CONCLUSIONS: Clinical characteristics, but not mode of pacing, were associated with subsequent stroke in patients paced for sinus node dysfunction.

Age Factors↗
PubMed2002

Effect of nesiritide (B-type natriuretic peptide) and dobutamine on ventricular arrhythmias in the treatment of patients with acutely decompensated congestive heart failure: the PRECEDENT study.

BACKGROUND: Dobutamine is commonly used as a means of treating decompensated congestive heart failure (CHF). Although typically effective at improving short-term hemodynamics and symptomatology, the frequent occurrence of arrhythmias and tachycardia is undesirable. In this randomized, multicenter trial, we compared the safety and clinical effectiveness of the cardiac hormone nesiritide (human B-type natriuretic peptide) with dobutamine in hospitalized patients with decompensated CHF. METHODS: The study population consisted of 255 patients who were randomized to 1 of 2 doses of intravenous nesiritide (0.015 or 0.03 microg/kg/min) or dobutamine (> or =5 microg/kg/min) and stratified by means of an earlier history of ventricular tachycardia. Patients were also assessed with 24 hour Holter recordings immediately before and during study drug therapy and by means of signs and symptoms of CHF. RESULTS: Dobutamine significantly increased the mean (1) number of ventricular tachycardia events per 24 hours by 48 +/- 205 (P =.001), (2) repetitive ventricular beats per hour by 15 +/- 53 (P =.001), (3) premature ventricular beats per hour by 69 +/- 214 (P =.006), and (4) heart rate by 5.1 +/- 7.7 beats per minute (P <.001). These end points were significantly decreased or unchanged in the nesiritide groups. Nesiritide did not increase heart rate, despite a greater reduction of blood pressure. Both drugs were similarly effective means of improving signs and symptoms of CHF. CONCLUSIONS: Dobutamine is associated with substantial proarrhythmic and chronotropic effects in patients with decompensated CHF, whereas nesiritide actually reduces ventricular ectopy or has a neutral effect. Compared with dobutamine, nesiritide may be a safer, short-term treatment for patients with decompensated CHF.

Aged↗
PubMedDate not supplied

Management of acute decompensated heart failure in the emergency department.

Heart failure, a disease of epidemic proportions, has a tremendous clinical and financial impact on the US health care system. With more than 5 million Americans diagnosed with heart failure and 5-year mortality approaching 50%, it is the most common cause of hospitalization in patients older than 65 years and is the single most expensive diagnosis in the US health care system. Because the average US hospital loses more than 1000 dollars per heart failure admission, effective therapies that decrease length of stay, reduce hospital costs, and prevent 30-day readmissions are needed. This article reviews the relevant pathophysiology of heart failure, discusses the newest diagnostic strategies for emergency department diagnoses, evaluates recent advances and effects of early aggressive therapies, and presents a suggested algorithm for the treatment of acutely decompensated heart failure in emergency departments.

Aged↗
PubMedDate not supplied

Long-term destination therapy with the HeartMate XVE left ventricular assist device: improved outcomes since the REMATCH study.

The Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure (REMATCH) trial demonstrated increased 1- and 2-year survival and improved quality of life for end-stage heart failure patients implanted with the HeartMate VE Left Ventricular Assist Device (LVAD) (Thoratec Corporation, Pleasanton, CA) compared with optimal medical management. This is the first report of Destination Therapy (DT) experience since REMATCH and incorporates improvements with the HeartMate XVE LVAD and patient management. Forty-two patients with end-stage heart failure at higher volume institutions were supported with the LVAD over a duration of 26.7 patient years (mean 232 days). Compared with REMATCH, DT patients had a 40% lower rate of death (0.49 vs. 0.84 deaths per patient year). Kaplan-Meier estimates of survival in the DT and REMATCH LVAD groups at 30 days were 90% and 81%, and at 1 year were 61% and 52%. The death rate due to sepsis was 8.3 times lower in DT patients (risk ratio, 0.12; 95% confidence interval, 0.02-0.90). DT patients were 2.1 times less likely to experience an adverse event (risk ratio, 0.47; 95% confidence interval, 0.35-0.63). These results demonstrate continued improvement with outcomes in long-term DT with LVADs. Given that these DT patients were similar to those in the REMATCH trial, the improved outcomes likely reflect improvements in the HeartMate XVE LVAD and experience with patient management.

Adult↗