Sumita D. Paul’s research while affiliated with Massachusetts General Hospital and other places

The objective of this study were to assess the impact of a quality assurance effort on the door-to-needle time and the choice of thrombolytic agent for the management of acute myocardial infarction in the emergency department. The study design involved a prospective collection of data on a series of consecutive patients who received a thrombolytic agent for a presumed acute myocardial infarction. The study was carried out in the emergency department of a major university urban tertiary care center. A total of 349 patients were studied from September 1989 to March 1994. The quality assurance program began in 1989 and included chart review of all patients receiving thrombolytic therapy, with special attention to all patients with door-to-needle times >60 minutes to identify causes for delay. Feedback was directed to pharmacy, nursing, and physician staff. Biannual reports were distributed throughout the hospital and the emergency department. Nursing-specific feedback led to the development of protocols for all aspects of the delivery of thrombolytic agents. The choice of thrombolytic agent was not dictated by the protocol, but the physician staff was continuously updated on the results of the latest clinical trials comparing one thrombolytic agent with another. The mean age was 58 years for men and 67 years for women in this cohort consisting of 78% men and 22% women. Thirty-seven percent of the myocardial infarctions were in an anterior location and 56% were in an inferior location. The median duration of chest pain before presentation to the emergency department was 120 minutes. Hospital mortality was 3%. Median door-to-needle time fell from 46 (1989–1991) to 36 (1992–1994) minutes, P 60 minutes decreased from 35% (1989–1991) to 16% (1992–1994) minutes, P

In a MEDLINE search of published English studies (1966 to 1996), no prior study was identified that examined gender-based differences in the management and prognosis of patients admitted with syncope. We studied 109 consecutive patients (48 women) admitted with syncope at the Massachusetts General Hospital (1989 to 1990). All patients underwent Holter monitoring, signal-averaged electrocardiography, and echocardiography according to study protocol. Follow-up was 100% complete (10 +/- 4 months). Women were older (74 +/- 2 vs 66 +/- 2 years, p <0.01) and less likely to have premonitory symptoms when compared with men (46% vs 66%, p <0.05). A greater proportion of men had left ventricular ejection fractions of <0.40 (18% vs 0%, p <0.01), abnormal signal-averaged electrocardiograms (28% vs 8%, p <0.01), and a cardiac cause for syncope (49% vs 25%, p <0.01). Although referral for diagnostic electrophysiologic testing was >3 times as frequent for men compared with women (20% of men vs 6% of women, p <0.05), this difference was not significant after adjustment for age, ventricular arrhythmia, and referral for coronary angiography. During follow-up, 21% of men versus 6% of women (p <0.05) had cardiac events (recurrent syncope, myocardial infarction, or sudden death). Cardiac event-free survival rates were worse for men (p = 0.045). Thus, we have identified gender-based differences in the clinical presentation of syncope for hospital admission. Left ventricular dysfunction and an abnormal signal-averaged electrocardiogram occur more frequently in men. Men are more likely to have cardiac syncope and worse cardiac event-free survival when compared with women.

Preoperative clinical indexes to stratify cardiac risk have not been validated angiographically. Our aims were to determine the concordance of clinical risk with severity of coronary stenosis and to develop and validate a preoperative clinical index to exclude the presence of significant coronary stenosis. We carried out a prospective study of 878 consecutive patients (including the derivation and validation sets). "Severe" stenosis was defined as three-vessel (> or = 50% stenosis in each), two-vessel (> or = 50% stenosis in one when the other is > or = 70% stenosis of the left anterior descending), or left main disease (> or = 50%); "critical" stenosis was three-vessel (> or = 70% stenosis in each) and/or left main stenosis > or = 70%. A preoperative clinical index (diabetes mellitus, prior myocardial infarction, angina, age > 70 years, congestive heart failure) was used to stratify patients. A gradient of risk for severe stenosis was seen with increasing numbers of clinical markers. The following prediction rules were developed: The absence of severe coronary stenoses can be predicted with a positive predictive value of 96% for patients who have no (1) history of diabetes, (2) prior angina, (3) previous myocardial infarction, or (4) history of congestive heart failure. The absence of critical coronary stenoses can be predicted with a positive predictive value of 94% for those who have no (1) prior angina, (2) previous myocardial infarction, or (3) history of congestive heart failure. By reliably identifying a large proportion of patients with a low likelihood of significant stenoses, these prediction rules can help to substantially reduce healthcare costs associated with preoperative cardiac risk assessment for noncardiac surgery.

Elderly patients have a higher mortality after acute myocardial infarction (MI) yet are treated less aggressively than younger patients. To determine (l) the risk-factor profiles, (2) presentation, (3) management, and (4) hospital outcomes for the elderly (> or = 75 years) compared with middle aged (66 to 74 years) and younger (< or = 65 years) patients in the 1990s, we studied 561 consecutive patients with acute MI. Compared with younger patients, the elderly more frequently had congestive heart failure (40 percent vs 14 percent; p < 0.00001) and non-Q wave infarctions (76 percent vs 56 percent; p < 0.005), received thrombolysis (9 percent vs 34 percent; p < 0.0001), and underwent catheterization (35 percent vs 73 percent; p < 0.00001), percutaneous transluminal coronary angioplasty (9 percent vs 31 percent; p < 0.0002), and coronary artery bypass grafting (5 percent vs 15 percent; p < 0.03) less frequently. Those who did not receive thrombolysis all had contraindications. Mortality was higher in the elderly (19 percent vs 5 percent; p < 0.004), especially among those who did not receive thrombolysis (20 percent vs 7 percent; p < 0.03). Multivariate predictors of mortality included age, and congestive heart failure. In addition, when clinical course and management variables were considered, use of the intraaortic balloon pump was a predictor of mortality, whereas undergoing coronary angiography was a negative predictor (relative risk, 0.3; 95 percent confidence intervals, 0.1 to 0.6).

Objectives: This study sought to develop and validate a Bayesian risk prediction model for vascular surgery candidates. Background: Patients who require surgical treatment of peripheral vascular disease are at increased risk of perioperative cardiac morbidity and mortality. Existing prediction models tend to underestimate risk in vascular surgery candidates. Methods: The cohort comprised 1,081 consecutive vascular surgery candidates at five medical centers. Of these, 567 patients from two centers ("training" set) were used to develop the model, and 514 patients from three centers were used to validate it ("validation" set). Risk scores were developed using logistic regression for clinical variables: advanced age (>70 years), angina, history of myocardial infarction, diabetes mellitus, history of congestive heart failure and prior coronary revascularization. A second model was developed from dipyridamole-thallium predictors of myocardial infarction (i.e., fixed and reversible myocardial defects and ST changes). Model performance was assessed by comparing observed event rates with risk estimates and by performing receiver-operating characteristic curve (ROC) analysis. Results: The postoperative cardiac event rate was 8% for both sets. Prognostic accuracy (i.e., ROC area) was 74 +/- 3% (mean +/- SD) for the clinical and 81 +/- 3% for the clinical and dipyridamole-thallium models. Among the validation sets, areas were 74 +/- 9%, 72 +/- 7% and 76 +/- 5% for each center. Observed and estimated rates were comparable for both sets. By the clinical model, the observed rates were 3%, 8% and 18% for patients classified as low, moderate and high risk by clinical factors (p<0.0001). The addition of dipyridamole-thallium data reclassified >80% of the moderate risk patients into low (3%) and high (19%) risk categories (p<0.0001) but provided no stratification for patients classified as low or high risk according to the clinical model. Conclusions: Simple clinical markers, weighted according to prognostic impact, will reliably stratify risk in vascular surgery candidates referred for dipyridamole-thallium testing, thus obviating the need for the more expensive testing. Our prediction model retains its prognostic accuracy when applied to the validation sets and can reliably estimate risk in this group.

Objectives. This study sought to determine how noninvasive and invasive cardiologists may differ in the hospital care of patients with acute myocardial infarction.Background. Scant information exists regarding the effect of noninvasive and invasive cardiology subspecialization on invasive cardiac procedural use, cost and outcome in the care of patients with acute myocardial infarction.Methods. This study analyzed a prospective cohort of 292 patients admitted to an urban tertiary care hospital from the emergency room under the care of noninvasive or invasive cardiologists. Clinical characteristics; hospital course, including management, utilization of diagnostic coronary angiography and percutaneous transluminal coronary angioplasty; direct hospital costs; length of hospital stay; and post-hospital discharge follow-up data were collected by a prospective data base instrument.Results. Despite similar clinical characteristics, extent and severity of coronary artery disease and utilization of diagnostic coronary angiography in the two groups of patients, those under the care of an invasive cardiologist were significantly more likely to undergo coronary angioplasty than those under the care of a noninvasive cardiologist. The direct hospital costs and length of stay of the noninvasive and invasive group patients who underwent coronary angioplasty were similar, although overall the direct hospital costs and length of stay were higher for the invasive than for the noninvasive group patients.Conclusions. Noninvasive and invasive cardiologists differ in their rate of utilization of coronary angioplasty in similar patients with acute myocardial infarction.

Previous studies have reported conflicting results on gender differences in the management of acute myocardial infarction (AMI) and have not evaluated hospital length of stay or costs. To determine gender-based differences in presentation, management, length of stay, costs, and prognosis after AMI, we studied 561 patients with AMI. Women were older, had systemic hypertension, diabetes mellitus, and a non-Q-wave AMI more frequently, whereas more men smoked cigarettes. Predictors of coronary angiography were: male gender (RR 1.9; 95% Cl 1.2 to 3.1), chest pain at presentation (RR 1.8; 95% Cl 1.0 to 3.3), recurrent angina (RR 4.1; 95% Cl 2.5 to 6.8), admission via the emergency room (RR 0.2; 95% Cl 0.1 to 0.3), and younger age. Gender did not predict mortality. Among presenting features, the predictors of length of stay were diabetes, prior coronary bypass and prior coronary angioplasty in men, and age alone in women. Pulmonary edema and need for coronary bypass during the hospital course were predictors of length of stay in men only. Among presenting features, predictors or cost were diabetes in men and congestive heart failure in women. Predictors of cost during hospitalization for men were pulmonary edema, coronary angiography, intraaortic balloon pump use, and coronary bypass; for women, they were peak levels of creatine kinase and coronary bypass. Thus, predictors of length of stay and hospitalization costs differ based on gender. Efforts at cost containment may need to be gender-specific.

Physicians should adapt a systematic approach to cardiac risk stratification for patients being considered for noncardiac surgery, involving clinical evaluation, functional assessment, and surgical risk assessment for all patients and then deciding which patient needs to undergo noninvasive testing, coronary angiography and revascularization, perioperative monitoring, and aggressive postoperative care.