The medical ethos and social responsibility in clinical medicine

The medical profession will face many challenges in the new millennium. As medicine looks forward to advances in molecular genetics and the prospect of unprecedented understanding of the causes and cures of human disease, clinicians, scientists and bioethicists may benefit from reflection upon the origins of the medical ethos and its relevance to postmodern medicine. Past distortions of the medical ethos, such as Nazism and the Tuskegee Syphilis Study, as well as more recent experience with the ethical challenges of employer-based market driven managed care, provide important lessons as medicine contemplates the future. Racial and ethnic disparities in health status and access to care serve as a reminders that the racial doctrines that fostered the horrors of the Holocaust and the Tuskegee Syphilis Study have not been completely removed from contemporary thinking. Inequalities in health status based on race and ethnicity, as well as socioeconomic status, attest to the inescapable reality of racism in America. When viewed against a background of historical distortions and disregard for the traditional tenets of the medical ethos, persistent racial and ethnic disparities and health and the prospect of genetic engineering raise the specter of discrimination because of genotype, a postmodern version of "racist medicine" or of a "new eugenics." There is a need to balance medicine's devotion to the wellbeing of the patient and the primacy of the patient-physician relationship against with the need to meet the health care needs of society. The challenge facing the medical profession in the new millennium is to establish an equilibrium between the responsibility to assure quality health care for the individual patient while affecting societal changes to achieve "health for all."

Medical ethos and social responsibility in clinical medicine

The medical profession will face many challenges in the new millenium. As medicine looks forward to advances in molecular genetics and the prospect of unprecedented understanding of the causes and cures of human disease, clinicians, scientists, and bioethicists may benefit from reflection on the origins of the medical ethos and its relevance to postmodern medicine. Past distortions of the medical ethos, such as Nazism and the Tuskegee Syphilis Study, as well as more recent experience with the ethical challenges of employer-based, market-driven managed care, provide important lessons as medicine contemplates the future. Racial and ethnic disparities in health status and access to care serve as reminders that the racial doctrines that fostered the horrors of the Holocaust and the Tuskegee Syphilis Study have not been removed completely from contemporary thinking. Inequalities in health status based on race and ethnicity, as well as socioeconomic status, attest to the inescapable reality of racism in America. When viewed against a background of historical distortions and disregard for the traditional tenets of the medical ethos, persistent racial and ethnic disparities in health and the prospect of genetic engineering raise the specter of discrimination because of genotype, a postmodern version of "racist medicine" or of a "new eugenics." There is a need to balance medicine's devotion to the well-being of the patient and the primacy of the patient-physician relationship against the need to meet the health care needs of society. The challenge facing the medical profession in the new millennium is to establish an equilibrium between the responsibility to ensure quality health care for the individual patient while effecting societal changes to achieve "health for all."

High levels of Lp(a) with a small apo(a) isoform are associated with coronary artery disease in African American and white men

Elevated levels of lipoprotein(a) [Lp(a)] and the presence of small isoforms of apolipoprotein(a) [apo(a)] have been associated with coronary artery disease (CAD) in whites but not in African Americans. Because of marked race/ethnicity differences in the distribution of Lp(a) levels across apo(a) sizes, we tested the hypothesis that apo(a) isoform size determines the association between Lp(a) and CAD. We related Lp(a) levels, apo(a) isoforms, and the levels of Lp(a) associated with different apo(a) isoforms to the presence of CAD (>/=50% stenosis) in 576 white and African American men and women. Only in white men were Lp(a) levels significantly higher among patients with CAD than in those without CAD (28.4 versus 16.5 mg/dL, respectively; P:=0.004), and only in this group was the presence of small apo(a) isoforms (<22 kringle 4 repeats) associated with CAD (P:=0.043). Elevated Lp(a) levels (>/=30 mg/dL) were found in 26% of whites and 68% of African Americans, and of those, 80% of whites but only 26% of African Americans had a small apo(a) isoform. Elevated Lp(a) levels with small apo(a) isoforms were significantly associated with CAD (P:<0.01) in African American and white men but not in women. This association remained significant after adjusting for age, diabetes mellitus, smoking, hypertension, HDL cholesterol, LDL cholesterol, and triglycerides. We conclude that elevated levels of Lp(a) with small apo(a) isoforms independently predict risk for CAD in African American and white men. Our study, by determining the predictive power of Lp(a) levels combined with apo(a) isoform size, provides an explanation for the apparent lack of association of either measure alone with CAD in African Americans. Furthermore, our results suggest that small apo(a) size confers atherogenicity to Lp(a).

Plasma sphingomyelin level as a risk factor for coronary artery disease

Only a fraction of the clinical complications of atherosclerosis are explained by known risk factors. Animal studies have shown that plasma sphingomyelin (SM) levels are closely related to the development of atherosclerosis. SM carried into the arterial wall on atherogenic lipoproteins may be locally hydrolyzed by sphingomyelinase, promoting lipoprotein aggregation and macrophage foam cell formation. A novel, high-throughput, enzymatic method to measure plasma SM levels has been developed. Plasma SM levels were related to the presence of coronary artery disease (CAD) in a biethnic angiographic case-control study (279 cases and 277 controls). Plasma SM levels were higher in CAD patients than in control subjects (60+/-29 versus 49+/-21 mg/dL, respectively; P:<0. 0001). Moreover, the ratio of SM to SM+phosphatidylcholine (PC) was also significantly higher in cases than in controls (0.33+/-0.13 versus 0.29+/-0.10, respectively; P:<0.0001). Similar relationships were observed in African Americans and whites. Plasma SM levels showed a significant correlation with remnant cholesterol levels (r=0.51, P:<0.0001). By use of multivariate logistic regression analysis, plasma SM levels and the SM/(SM+PC) ratio were found to have independent predictive value for CAD after adjusting for other risk factors, including remnants. The odds ratio (OR) for CAD was significantly higher for the third and fourth quartiles of plasma SM levels (OR 2.81 [95% CI 1.66 to 4.80] and OR 2.33 [95% CI 1.38 to 3. 92], respectively) as well as the SM/(SM+PC) ratio (OR 1.95 [95% CI 1.10 to 3.45] and OR 2.33 [95% CI 1.34 to 4.05], respectively). The findings indicate that human plasma SM levels are positively and independently related to CAD. Plasma SM levels could be a marker for atherogenic remnant lipoprotein accumulation and may predict lipoprotein susceptibility to arterial wall sphingomyelinase.

Hypertensive vascular disease as a cause of death in blacks versus whites: autopsy findings in 587 adults

Cardiovascular disease is the major cause of excess mortality among urban US blacks, but autopsy data comparing black-white differences in underlying pathological causes of cardiovascular death are lacking. We reviewed all 720 adult cases autopsied in 1991 in the New York City Medical Examiner's Office in which the coded cause of death was cardiovascular disease (International Classification of Diseases, 9th Revision, codes 391, 393 to 398, 401 to 404, 410, 411, 414 to 417, 420 to 438, and 440 to 444). After exclusion of 133 cases because race was missing or coded as other than black or white, gender was not coded, or there was an unusual circumstances of death or extreme obesity, 587 cases were available for analysis. There were 314 black and 273 white subjects. Black women were younger than white women at time of death (mean age, 54.7 versus 61.5 years; P<.001), whereas black and white men did not differ in mean age at death. Hypertensive vascular disease was the autopsy cause of death in 42% of blacks compared with 23% of whites (P<.001). Conversely, atherosclerotic heart disease was the autopsy cause of death in 64% of white subjects but only 38% of blacks. These patterns were consistent in both sexes and after adjustment for age. Hypertensive vascular disease was far more common than atherosclerotic heart disease as the cause of death at autopsy among blacks compared with whites in New York City, whereas atherosclerotic heart disease was more common in whites. These findings suggest that ineffective control of hypertension is a major factor contributing to excess cardiovascular mortality among urban blacks.

Research in coronary heart disease in blacks: issues and challenges

Research on coronary heart disease (CHD) has contributed to the decline in cardiovascular disease morbidity and mortality during the past three decades. However, life expectancy and rates of illness and death from CHD have not improved for blacks as for whites. Blacks have not experienced the full benefit of research advancements for a variety of reasons, including insufficient scientific data, lack of research focused on minority populations, and limited access to health care resources and technology. In order to address these disparities in prevention, diagnosis, treatment, and outcomes of CHD in blacks, the National Heart, Lung, and Blood Institute converted a Working Group on Research in Coronary Heart Disease in Blacks. In its deliberations, the working group identified 10 priority research areas, which are treatment, epidemiology (data collection and analysis), evaluation of chest pain and diagnosis of CHD, prevention and behavior, risk factors, genetics, vascular biology, left ventricular hypertrophy, coronary microvasculature, and sudden cardiac death.

Coronary revascularization and cardiac catheterization in the United States: trends in racial differences

OBJECTIVES

We sought to determine whether racial differences in rates of coronary artery bypass graft surgery (CABG), percutaneous transluminal coronary angioplasty (PTCA) and cardiac catheterization decreased after 1980.

BACKGROUND

Many reports of racial differences in utilization of CABG have been published since 1982. However, changes in the relative utilization of revascularization over time have received little attention.

METHODS

Data from the National Hospital Discharge Survey were examined for the years 1980 through 1993. Estimated numbers of procedures performed in nonfederal U.S. hospitals were used to compute age-adjusted rates per 100,000 population by year and race for patients 35 to 84 years old.

RESULTS

In patients 35 to 84 years old, the rate of CABG increased in blacks and whites between 1980 and 1993. Between 1986 and 1993, there was little change in the black/white ratio of age-adjusted rates (0.23 in 1980 through 1985 combined, 0.38 in 1986 and 0.43 in 1993). An apparent increase from 0.23 in 1980 through 1985 combined may have been due to sampling variation. Despite rapid increases in rates of PTCA in both races, no increase in the black/white ratio was noted (0.57 in 1993). However, the rate of inpatient cardiac catheterization increased more rapidly in blacks than in whites. This resulted in an increase in the black/white ratio of age-adjusted rates from 0.42 in 1980 to 0.91 in 1993.

CONCLUSIONS

Rates of CABG, cardiac catheterization and especially PTCA increased between 1980 and 1993, a period during which racial disparities in the procedures became widely known. Despite apparent increases in the black/white ratio for inpatient cardiac catheterization, large racial disparities in the utilization of CABG and PTCA persist and require further evaluation and possible intervention.

New staging system of the fifth Joint National Committee report on the detection, evaluation, and treatment of high blood pressure (JNC-V) alters assessment of the severity and treatment of hypertension

The fifth Joint National Committee report on the detection, evaluation, and treatment of high blood pressure (JNC-V) introduced a new system of blood pressure classification that incorporated systolic blood pressure (SBP) and established new diastolic blood pressure (DBP) cut points. With the previous JNC classification, subjects were classified according to DBP alone. In this study, our purpose was to assess the effect of the new staging system on the assessment of hypertension severity and to determine whether' the new JNC-V staging system better identifies individuals at risk for hypertensive target-organ damage. We compared the assessment of hypertension severity using JNC-IV with that using JNC-V in 1158 subjects enrolled in the Harlem Hospital Hypertension Clinic database from 1975 to 1992. We used pretreatment DBP to classify subjects according to JNC-IV criteria. These subjects were reclassified into one of the four stages of JNC-V. The assessment of hypertension severity and prevalence of organ damage in subjects who remained in the same category of severity in both systems was compared with damage in subjects who were upstaged. With the JNC-V classification, 321 subjects remained in the same category, and 837 were upstaged. Six hundred and four subjects moved up because of the new cut points of DBP, and 275 were upstaged because of higher SBP. Upstaged subjects had more manifestations of hypertensive target-organ damage. With the new JNC-V classification system, hypertension is assessed as severe or very severe in more individuals than with JNC-IV. Subjects who are upstaged in JNC-V are more likely to have evidence of renal disease and other target-organ damage.

Acceptance and use of Put Prevention into practice materials at an inner-city hospital

Many studies indicate that physicians' prevention practices frequently differ from published guidelines. Put Prevention into Practice (PPIP) consists of a variety of paper-based materials for providers, patients, and the office setting designed to enhance the delivery of clinical preventive services. Prototype PPIP materials were distributed to physicians and patients at the Harlem Hospital medical clinic in conjunction with a series of prevention lectures for physicians. Acceptance and use of these materials were assessed through self-administered questionnaires for physicians and structured interviews for patients. A regression analysis was conducted to assess correlates of physician use of PPIP materials. Physicians reported a high degree of use of and satisfaction with PPIP materials. Multiple regression analysis indicated that the physicians' perceived self-efficacy in their ability to provide preventive counseling to patients at baseline was significantly associated with increased use of PPIP materials. When controlling for baseline physician self-efficacy, physicians whose self-efficacy increased during the study period were more likely to have used the materials. A majority of patients (53%) reported that the main patient-based component of the program-a pocket-sized booklet providing health education information and record-keeping of preventive tests and procedures-was very useful. Results from this study indicate a high degree of acceptance of prototype PPIP materials by physicians and patients at an inner-city hospital. Educational programs for physicians that enhance physician self-efficacy may be more effective in helping practitioners to adopt office-based prevention resources. Medical Subject Headings (MeSH): prevention, primary care, preventive health services, clinical practice patterns.

Hemodynamic correlates of spontaneous echo contrast in the descending aorta

To identify the hemodynamic association of spontaneous echo contrast (SEC) in the descending aorta (DA), we measured aortic flow parameters in 102 consecutive patients studied with transesophageal echocardiography. SEC in the DA was identified in 19 of 102 patients (19%). Patients with SEC in the DA were older (67 +/- 9 vs 57 +/- 17 years; p = 0.001), had a higher proportion of chronic atrial arrhythmia (13 of 19 vs 11 of 83; p = 0.000001), and had a higher frequency of decreased left ventricular performance (10 of 19 vs 19 of 83; p = 0.01). Patients with SEC in the DA had larger aortic diameters (2.9 +/- 0.5 vs 2.3 +/- 0.4 cm; p = 0.0001), lower maximal velocity in the DA (42.6 +/- 12.8 vs 75.6 +/- 34.4 cm/s; p = 0.0001), and lower maximal shear rate (61.6 +/- 20.3 vs 139.9 +/- 78.8 s-1; p = 0.0001). There was no difference in volumetric flow in the DA between groups. In multivariate analysis, only arrhythmia (p = 0.008) and maximal shear rate (p = 0.002) were identified as significant independent predictors of SEC in the DA. We conclude that SEC in the DA is related to chronic atrial arrhythmia and shear rate but not to volumetric flow.

Task Force 1: The underserved

The ACC has affirmed its commitment to universal access to health care. Underserved populations exist in urban and rural centers. Common to each is a paucity of personnel trained in cardiovascular care and a lack of access to preventive and highly technologic services. These factors contribute to a poor health outcome (75). Part of the rural problem can be corrected by the transfer of information to local providers by the use of new information systems. Included would be real-time electronic consultation, on-site subspecialty visits and the appropriate use of nonphysician providers (15). The urban problem requires changes in priorities and responsibilities of the academic health centers toward the communities they serve. Curricula changes of cardiovascular specialists, internists, generalists and nonphysician health care personnel must include diversity in training, physician training of ethnically matched providers in addition to technical excellence and research into methods of patient education and motivation for a healthier life-style (51). Reimbursement must appropriately reward those caring for underserved patients and those providing evaluation and management services (43,52).

Effect of thrombolysis on acute mitral regurgitation during evolving myocardial infarction. Experience from the Thrombolysis in Myocardial Infarction (TIMI) Trial

OBJECTIVES

This study was undertaken to determine whether early successful thrombolysis can reverse infarct-associated mitral valve dysfunction.

BACKGROUND

Mitral regurgitation is a common complication of acute myocardial infarction and has been shown to adversely affect both short- and long-term prognosis. Although anecdotal reports have suggested that reperfusion of the infarct-related artery may restore normal function to the mitral valve, this theory has not been subjected to formal investigation.

METHODS

Patients with total or partial obstruction of the infarct-related artery received intravenous thrombolytic therapy with either streptokinase or recombinant tissue-type plasminogen activator within 7 h of symptom onset (mean 4.8 h) as part of the Thrombolysis in Myocardial Infarction (TIMI) Phase I trial. Repeat coronary angiography assessed arterial patency at 90 min and 10 days after attempted reperfusion. The presence and severity of mitral regurgitation were determined by contrast ventriculography both before thrombolysis and before hospital discharge.

RESULTS

Overall, 21 (16%) of the 132 study patients exhibited mitral regurgitation on either their initial or their predischarge ventriculogram. The proportion of infarct-related arteries found to be patent (TIMI flow grade 2 or 3) was statistically similar in patients with and without mitral regurgitation during each angiographic evaluation period (initial, 90 min and 10 days). Although coronary artery perfusion increased overall during sequential measurement (mean TIMI grade was 0.4 +/- 0.6 initially, 1.5 +/- 1.3 at 90 min and 2.2 +/- 1.0 at 10 days), the pattern of reperfusion observed could not predict an increase or decrease in regurgitant severity (p = NS). Early mitral regurgitation resolved in 57% of patients by 10 days, but this resolution appeared independent of the presence or absence of improved coronary perfusion (60% vs. 50%). The development of new regurgitation during the recovery period (6%) was also unrelated to improved perfusion (7% vs. 4%).

CONCLUSIONS

Acute mitral regurgitation developing during myocardial infarction shows frequent changes in its presence or severity during the 1st 10 days, appears independent of coronary artery patency both early and late after thrombolysis and cannot be reliably treated by improving arterial perfusion with thrombolytic agents.

Correlates of nonadherence to hypertension treatment in an inner-city minority population

OBJECTIVE

Adherence to treatment is a key factor in achieving blood pressure control among hypertensives. We examined correlates of nonadherence to hypertension treatment in an inner-city minority population.

METHODS

Subjects (n = 202) were interviewed as part of a case-control study of severe, uncontrolled hypertension conducted in two New York City hospitals in 1989-91. All subjects were African American or Hispanic. Self-reported nonadherence to drug treatment for hypertension was measured using a five-item scale, and the sample was dichotomized as more (n = 87) or less (n = 115) adherent. Multiple logistic regression analysis was used to adjust for demographic and other covariates.

RESULTS

Nonadherence was associated with having blood pressure checked in an emergency room (adjusted odds ratio [OR] = 7.9; 95% confidence interval [CI] = 1.75, 35.77; P < .01), lack of a primary care physician (adjusted OR = 2.9; 95% CI = 1.37, 6.02; P < .01), current smoking (adjusted OR = 2.4; 95% CI = 1.10, 5.22; P = .03), and younger age (adjusted OR = 1.03, 95% CI = 1.00, 1.06; P = .03).

CONCLUSIONS

Changing the locus of care for hypertension from emergency rooms to primary care physicians may improve adherence to hypertension treatment in minority populations.

Predisposing factors for severe, uncontrolled hypertension in an inner-city minority population

BACKGROUND

Hypertensive emergency and urgent hypertension are the most severe forms of uncontrolled hypertension and are now seen predominantly in poor, minority populations. We studied the characteristics of the medical care received by patients with these conditions in order to identify risk factors for severe, uncontrolled hypertension.

METHODS

Using a case-control study design, we interviewed 93 patients with severe, uncontrolled hypertension who presented in the hospital emergency room and 114 control patients with hypertension; both groups were seen at two New York City hospitals from 1989 through 1991. All the patients were black or Hispanic. Multiple logistic-regression models were used to adjust for age, sex, race or ethnic background, education, smoking status, alcohol-related problems, and use of illicit drugs during the previous year.

RESULTS

After additional adjustment for lack of health insurance, severe, uncontrolled hypertension was found to be more common among patients who had no primary care physician (adjusted odds ratio, 3.5; 95 percent confidence interval, 1.6 to 7.7) and among those who did not comply with treatment for their hypertension (adjusted odds ratio, 1.9; 95 percent confidence interval, 1.4 to 2.5). Lack of health insurance was marginally associated with severe, uncontrolled hypertension (adjusted odds ratio, 1.9; 95 percent confidence interval, 0.8 to 4.6) after adjustment for lack of a primary care physician and noncompliance with antihypertensive treatment. Patients without a primary care physician and without health insurance were more likely to have their blood pressure checked and receive prescriptions for blood-pressure medications in emergency rooms than in physicians' offices or clinics.

CONCLUSIONS

Characteristics of both the health care system and patients' behavior are associated with severe, uncontrolled hypertension. Improving access to primary care physicians, through health insurance or other means, may be an effective strategy for improving control of hypertension in disadvantaged minority populations.

Mitral regurgitation in early myocardial infarction. Incidence, clinical detection, and prognostic implications. TIMI Study Group

OBJECTIVE

To investigate mitral regurgitation occurring early in the course of acute myocardial infarction with respect to its incidence, the impact of infarct size and location, the accuracy of clinical detection, the contribution of global and regional left ventricular performance, and its influence on prognosis.

DESIGN

Prospective observational study derived from patients entering Phase I of the Thrombolysis in Myocardial Infarction (TIMI) trial.

SETTING

Multicenter trial involving 13 university-affiliated medical centers.

PATIENTS

A total of 206 patients studied within 7 hours of symptom onset during their first myocardial infarction.

MEASUREMENTS

Contrast left ventriculography was used to document mitral regurgitation.

RESULTS

Mitral regurgitation was present in 27 patients (13%). Although the presence of regurgitation correlated with the site of infarction (20 of 27 had anterior infarctions) and the number of akinetic chords, it was not statistically related to the peak creatine kinase value or to left ventricular chamber size or filling pressure. A murmur of mitral regurgitation was heard in only 2 patients (1 incorrectly). The presence of early mitral regurgitation predicted cardiovascular mortality at 1 year by univariate (relative risk, 12.2; 95% Cl, 3.5 to 42; P less than 0.0001) and multivariate (relative risk, 7.5; Cl, 2.0 to 28.6; P = 0.0008) analyses.

CONCLUSIONS

Mitral regurgitation in early myocardial infarction is generally clinically "silent," is more common in anterior infarction, is associated with regional dysfunction but not early ventricular dilation or peak enzyme release, and is an important predictor of cardiovascular mortality.

Hypertension, cardiac disease, and compliance in minority patients

In minorities, as in the general population, hypertension is taken seriously because it is a risk factor for cardiovascular disease. Until recently, our understanding of the role that hypertension plays in the heart disease seen in minorities has been limited by a paucity of prospective data regarding the prevalence, natural history, and pathophysiology of the disease process in minority populations. In the last few years large-scale epidemiologic studies and well-controlled clinical studies alike have confirmed usually high rates of hypertension-related morbidity and mortality in minorities, particularly blacks and Hispanics. The severity of end-organ damage, both cardiac and renal, that is seen in these patients--especially when coupled with the severe cerebrovascular damage that is also more common in black and Hispanic hypertensives--mandate that more effective public health measures be taken to reduce the incidence of hypertension in these patient populations. Because hypertension is usually without significant clinical symptoms, noncompliance with drug therapy and high dropout rates are common in all patient populations. They are strikingly higher in inner-city populations, however, where illiteracy, poverty, homelessness, and high rates of chemical dependency combine to exacerbate an already serious problem in treating hypertensive patients. Inner-city patients are, increasingly, black and Hispanic patients, and these patients are more likely to be underinsured or uninsured, to be functionally illiterate in English, to be disinclined to seek health care, and to be less capable of following a prescribed regimen than the populace as a whole. The nature of the therapeutic regimen itself is probably the most important determinant of compliance, and compliance with drug therapy will be improved if the clinic chooses a simplified drug regimen and avoids drugs that produce intolerable side effects. Once-a-day--or, with transdermal clonidine, one-a-week--single-drug therapy may not be possible in all patients, but multiple drug therapy and multiple daily dosing schedules should be avoided wherever possible.

Improving compliance in an inner-city hypertensive patient population

Because hypertension is a "silent" disease process, compliance with therapy is always a problem. In the inner city, where socioeconomic factors such as poverty, illiteracy, and substance abuse raise additional barriers to effective health care, poor compliance with antihypertensive regimens can reach epidemic proportions--as it did in our clinic in the early 1970s. After identifying the major causes of poor compliance in our patients, we instituted measures that led directly to greatly improved compliance and control, among them the expansion of clinic hours, the expediting of laboratory services, and the training of nurse-therapists to assume many of the responsibilities of running the clinic. In recent years a number of new antihypertensive agents have been introduced, and these new drugs have afforded patients better blood pressure control through less complex drug regimens with fewer serious side effects. Indeed, we observed a strong correlation between patient compliance and the administration of agents with longer dosing intervals and improved side effects profiles. This observation led us to consider whether transdermal clonidine--which requires weekly, rather than daily, administration--might not be an especially effective means of controlling blood pressure in inner-city patients. To test this hypothesis, we enrolled 20 patients, all of them blacks, in a pilot study of this unique delivery system. Blood pressure was adequately controlled in all 18 patients who completed the study, and patients were uniformly enthusiastic about this alternative to daily dosing. As a result, compliance with this mode of therapy was excellent.

Cardiac involvement in AIDS

Cardiac involvement in AIDS may occur at any stage of HIV disease and may manifest as congestive cardiomyopathy, potentially lethal arrhythmia, or pericardial effusion and tamponade. The heart may be affected by nearly all of the opportunistic infections and many of the malignancies associated with the syndrome. Although often clinically unobtrusive, cardiac lesions may be important in the pathogenesis of significant clinical symptoms and play an often unrecognized role in the prognosis and natural history of AIDS.

Hypertension and cardiac disease in minorities

Despite recent advances in both prevention and treatment, cardiovascular disease remains the leading cause of mortality in the United States. One of the major modifiable risk factors for cardiovascular disease, hypertension, is a leading cause of stroke, kidney disease, and diseases of the heart and coronary circulation. Essential hypertension is the most common cause of systemic blood pressure elevation and it responds readily to both pharmacologic and non-pharmacologic treatment. More patients visit physicians and receive prescriptions for the treatment of hypertension than for any other medical disorder. Nevertheless, more than a million Americans die each year from the direct or indirect effects of hypertension. Over the last two decades, significant progress has been made in reducing mortality from cardiovascular disease. Through public health programs like the National High Blood Pressure Education Program, increasing numbers of hypertensive patients have been detected, treated and controlled. As a result, the number of deaths from stroke, kidney disease, and coronary artery disease has declined significantly. For both blacks and Hispanics, however, the decreases in cardiovascular mortality have been less striking. Many factors could account for this disparity, among them the availability of health care facilities in minority neighborhoods, and the health-care-seeking behavior of the patients themselves. Understanding epidemiologic and pathophysiologic data regarding differences between blacks, Hispanics, and non-Hispanic whites will help reduce hypertension-related morbidity and mortality.

Left ventricular function in ischemic mitral regurgitation--a precatheterization assessment

The clinical characteristics of 150 patients with unstable ischemic heart disease were evaluated for the ability to diagnose mitral regurgitation (MR). A careful assessment of physical findings, ECG- and radionuclide-determined global and regional left ventricular function was performed in all patients to characterize the population with ischemic MR. Twenty-nine patients were found to have MR and in 65% the degree of MR was 2+ or more. All of the patients with significant MR had a systolic murmur on physical examination, and although this finding was 90% sensitive for MR it had a poor predictive value (42%). Even a characteristic apical holosystolic murmur, although specific for MR (90%), had a low sensitivity and predictive value. Two regional wall motion abnormalities (inferoposterior akinesis and apical dyskinesis with an ejection fraction less than or equal to 35%) identified 26 of 29 patients with MR and all with 2+ or more MR, as well as the 10 patients who required mitral valve replacement in addition to coronary artery bypass grafting. This finding was complementary to the results of physical examination and when used together improved the diagnostic accuracy of identifying MR. The radionuclide regurgitant index was evaluated for its predictive value in assessing MR in this group of patients but was found to be a poor discriminator in patients with abnormal ejection fractions and regional wall motion abnormalities. The precatheterization assessment of left ventricular function with radionuclide angiography can provide important insight into the presence of ischemic MR.

Thallium-201 stress imaging in hypertensive patients

To assess the potential effect of hypertension on the results of thallium-201 stress imaging in patients with chest pain, 272 thallium-201 stress tests performed in 133 hypertensive patients and 139 normotensive patients over a 1-year period were reviewed. Normotensive and hypertensive patients were similar in age, gender distribution, prevalence of cardiac risk factors (tobacco smoking, hyperlipidemia, and diabetes mellitus), medications, and clinical symptoms of coronary disease. Electrocardiographic criteria for left ventricular hypertrophy were present in 16 hypertensive patients. Stepwise probability analysis was used to determine the likelihood of coronary artery disease for each patient. In patients with mid to high likelihood of coronary disease (greater than 25% probability), abnormal thallium-201 stress images were present in 54 of 60 (90%) hypertensive patients compared with 51 of 64 (80%) normotensive patients. However, in 73 patients with a low likelihood of coronary disease (less than or equal to 25% probability), abnormal thallium-201 stress images were present in 21 patients (29%) of the hypertensive group compared with only 5 of 75 (7%) of the normotensive patients (p less than 0.001). These findings suggest that in patients with a mid to high likelihood of coronary artery disease, coexistent hypertension does not affect the results of thallium-201 exercise stress testing. However, in patients with a low likelihood of coronary artery disease, abnormal thallium-201 stress images are obtained more frequently in hypertensive patients than in normotensive patients.

Thrombolysis in Myocardial Infarction (TIMI) Trial, Phase I: A comparison between intravenous tissue plasminogen activator and intravenous streptokinase. Clinical findings through hospital discharge

Intravenous administration of 80 mg of recombinant tissue plasminogen activator (rt-PA, 40, 20, and 20 mg in successive hours) and streptokinase (SK, 1.5 million units over 1 hr) was compared in a double-blind, randomized trial in 290 patients with evolving acute myocardial infarction. These patients entered the trial within 7 hr of the onset of symptoms and underwent baseline coronary arteriography before thrombolytic therapy was instituted. Ninety minutes after the start of thrombolytic therapy, occluded infarct-related arteries had opened in 62% of 113 patients in the rt-PA and 31% of 119 patients in the SK group (p less than .001). Twice as many occluded infarct-related arteries opened after rt-PA compared with SK at the time of each of seven angiograms obtained during the first 90 min after commencing thrombolytic therapy. Regardless of the time from onset of symptoms to treatment, more arteries were opened after rt-PA than SK. The reduction in circulating fibrinogen and plasminogen and the increase in circulating fibrin split products at 3 and 24 hr were significantly less in patients treated with rt-PA than in those treated with SK (p less than .001). The occurrence of bleeding events, administration of blood transfusions, and reocclusion of the infarct-related artery was comparable in the two groups. Thus, in patients with acute myocardial infarction, rt-PA elicited reperfusion in twice as many occluded infarct-related arteries as compared with SK at each of seven serial observations during the first 90 min after onset of treatment.

Reactivation of herpesvirus in neurosurgical patients

The authors are presenting seven patients who had operations between July 1984 and July 1985 and who developed herpes infections postoperatively. Four of the patients developed their infections in a dermatomal distribution that correlated with the nerve roots manipulated at operation. A spectrum of localized herpes reactivation is demonstrated in this series. The use of corticosteroids and other associated variables are discussed. Like reactivation of herpes simplex after trigeminal nerve operation, we believe reactivation of herpes simplex and herpes zoster can occur in operation of the cervical, thoracic, or lumbosacral spine.

An improved index of left ventricular function in chronic mitral regurgitation

The ratio of end-systolic wall stress (ESWS) to volume index (ESVI) has been proposed as a useful index of left ventricular (LV) function in chronic mitral regurgitation (MR). However, although this ratio reflects isometric contraction, the chronic changes in LV architecture caused by MR may affect its usefulness. An index was evaluated that incorporated the ejection fraction--(TVEF [tension-volume ejection fraction] = ESWS/ESVI X EF)--thus combining both isometric and ejection phase parameters. Forty patients with symptomatic MR but no other valvular or coronary disease had valve replacement between 1980 and 1984. Twenty-nine patients (group A) were in New York Heart Association class I or II postoperatively. The remaining patients (group B) were in class III or IV or died. Four preoperative LV function indexes were compared. The means of all indexes in groups A and B were significantly different, but only TVEF completely separated the groups. A TVEF of less than 1.47 uniformly predicted a poor operative outcome.

Intravenous recombinant tissue-type plasminogen activator in patients with acute myocardial infarction: a report from the NHLBI thrombolysis in myocardial infarction trial

The efficacy and safety of a 3 hr, 80 mg intravenous infusion of recombinant tissue-type plasminogen activator (rt-PA) were investigated in 47 patients with acute myocardial infarction. Coronary angiography, performed before the administration of rt-PA and for 90 min thereafter, demonstrated that 37 patients had total coronary occlusion before therapy. After 90 min of rt-PA (50 mg), reperfusion of the infarct-related artery was observed in 25 patients (68%). Continuous infusions of heparin for anticoagulation were administered for 8 to 10 days. Of 36 patients who underwent follow-up coronary cineangiography, 21 had initially presented with total occlusion and had experienced reperfusion at 90 min. Sustained perfusion of the infarct-related artery was observed in 14 (67%) of these 21 initially reperfused patients. Late angiography was performed in nine patients who initially demonstrated subtotal occlusion of the infarct-related artery; sustained perfusion was observed in eight (89%). Significant bleeding was observed in 15 patients (32%). A hematoma at the site of the acute catheterization accounted for most instances of significant bleeding (11/15, 73%). Administration of rt-PA resulted in a significant decline in fibrinogen and plasminogen while amounts of fibrin(ogen) degradation products rose. In no patient, however, did fibrinogen levels decline to less than 140 mg/dl. Thus, rt-PA, administered as a brief 80 mg intravenous infusion, is capable of restoring blood flow in a high proportion of patients with acute myocardial infarction due to total coronary obstruction. Declines in plasma fibrinogen and plasminogen are observed. If combined with heparin anticoagulation and invasive vascular procedures, significant bleeding is a common complication.(ABSTRACT TRUNCATED AT 250 WORDS)

High dose intravenous streptokinase for acute myocardial infarction: preliminary results of a multicenter trial

To assess the efficacy of intravenous streptokinase in patients with acute myocardial infarction, 40 patients (30 men and 10 women, mean age 54 years) with acute myocardial infarction were given 1.5 million U of streptokinase intravenously in 1 hour, and coronary arteriography was performed repeatedly to assess reperfusion. Streptokinase treatment was begun 270 +/- 86 (mean +/- SD) minutes after the onset of chest pain. Of the 40 patients, 34 had total or near total coronary occlusion before streptokinase administration. In 14 (41%) of these 34 patients, some reperfusion occurred during the 90 minutes after the administration of streptokinase, but in only 11 of the 14 was reperfusion present at 90 minutes. After streptokinase administration, all patients received heparin for 8 to 10 days; they were subsequently administered aspirin and dipyridamole. Clinical evidence of reocclusion during the first 24 hours of heparin therapy occurred in one patient. Thus, when given to patients with acute myocardial infarction and total coronary occlusion an average of 4 1/2 hours after the onset of chest pain, high dose intravenous streptokinase achieves reperfusion in only about 40% and results in sustained reperfusion in only about 30%.

Regulation of myocardial amino acid balance in the conscious dog

The effects in vivo of physiologic increases in insulin and amino acids on myocardial amino acid balance were evaluated in conscious dogs. Arterial and coronary sinus concentrations of amino acids and coronary blood flow were measured during a 30-min basal and a 100-min experimental period employing three protocols: euglycemic insulin clamp (plasma insulin equaled 70 +/- 11 microU/ml, n = 6); euglycemic insulin clamp during amino acid infusion (plasma insulin equaled 89 +/- 12 microU/ml, n = 6); and suppression of insulin with somatostatin during amino acid infusion (plasma insulin equaled 15 +/- 4 microU/ml, n = 6). Basally, only leucine and isoleucine were removed significantly by myocardium (net branched chain amino acid [BCAA] uptake equaled 0.5 +/- 0.2 mumol/min), while glycine, alanine, and glutamine were released. Glutamine demonstrated the highest net myocardial production (1.6 +/- 0.2 mumol/min). No net exchange was seen for valine, phenylalanine, tyrosine, cysteine, methionine, glutamate, asparagine, serine, threonine, taurine, and aspartate. In group I, hyperinsulinemia caused a decline of all plasma amino acids except alanine; alanine balance switched from release to an uptake of 0.6 +/- 0.4 mumol/min (P less than 0.05), while the myocardial balance of other amino acids was unchanged. In group II, amino acid concentrations rose, and were accompanied by a marked rise in myocardial BCAA uptake (0.4 +/- 0.1-2.6 +/- 0.3 mumol/min, P less than 0.001). Uptake of alanine was again stimulated (0.9 +/- 0.3 mumol/min, P less than 0.01), while glutamine production was unchanged (1.3 +/- 0.4 vs. 1.6 +/- 0.3 mumol/min). In group III, there was a 4-5-fold increase in the plasma concentration of the infused amino acids, accompanied by marked stimulation in uptake of only BCAA (6.8 +/- 0.7 mumol/min). Myocardial glutamine production was unchanged (1.9 +/- 0.4-1.3 +/- 0.7 mumol/min). Within the three experimental groups there were highly significant linear correlations between myocardial uptake and arterial concentration of leucine, isoleucine, valine, and total BCAA (r = 0.98, 0.98, 0.92, and 0.97, respectively); P less than 0.001 for each). In vivo, BCAA are the principal amino acids taken up by the myocardium basally and during amino acid infusion. Plasma BCAA concentration and not insulin determines the rate of myocardial BCAA uptake. Insulin stimulates myocardial alanine uptake. Neither insulin nor amino acid infusion alters myocardial glutamine release.

Regulation by insulin of myocardial glucose and fatty acid metabolism in the conscious dog

In vivo small doses of insulin inhibit lipolysis, lower plasma FFA, and stimulate glucose disposal. Lowering of plasma FFA, either in the absence of a change in insulin or during combined hyperglycemia and hyperinsulinemia, promotes glucose uptake by heart muscle in vivo. In the isolated perfused heart, large doses of insulin directly stimulate heart glucose uptake. To assess the effect of physiological elevations of plasma insulin upon myocardial glucose and FFA uptake in vivo independent of changes in plasma substrate concentration, we measured arterial and coronary sinus concentrations of glucose, lactate, and FFA, and coronary blood flow in conscious dogs during a 30 min basal and a 2 h experimental period employing three protocols: (a) euglycemic hyperinsulinemia (insulin clamp, n = 5), (b) euglycemic hyperinsulinemia with FFA replacement (n = 5), (c) hyperglycemic euinsulinemia (hyperglycemic clamp with somatostatin, n = 5). In group 1, hyperinsulinemia (insulin = 73 +/- 13 microU/ml) stimulated heart glucose uptake (7.3 +/- 4.4 vs. 28.2 +/- 2.8 mumol/min, P less than 0.002), lowered plasma FFA levels by 80% (P less than 0.05), and decreased heart FFA uptake (28.4 +/- 4 vs. 1.5 +/- 0.9, P less than 0.01). When the fall in plasma FFA was prevented by FFA infusion (group 2), hyperinsulinemia (86 +/- 10 microU/ml) provoked a lesser (P less than 0.05) stimulation of glucose uptake (delta = 8.2 +/- 4.2 mumol/min) than in group 1, and there was no significant change in FFA uptake (25.3 +/- 16 vs. 16.5 +/- 4). Hyperglycemia (plasma glucose = 186 +/- 8 mg/100 ml) during somatostatin infusion resulted in only a small rise in plasma insulin (delta = 12 +/- 7 microU/ml), and although plasma FFA tended to decline, heart glucose uptake did not rise significantly (delta = 5.5 +/- 3.2 mumol/min, P = NS). There was no significant change in coronary blood flow during any of the three study protocols. We conclude that, in the dog, insulin at physiologic concentrations: (a) stimulates heart glucose uptake, both directly and by suppressing the plasma FFA concentration, and (b) does not alter coronary blood flow. Hyperglycemia per se has little effect on heart glucose uptake.

Combined valve replacement and myocardial revascularization

Combining valve replacement with coronary artery bypass (CABG) for significant concomitant disease remains a controversial subject. To determine the operative results following combined valve replacement and CABG, we evaluated 201 patients seen consecutively between July 1977 and June 1982. CABG for vessels with greater than 70% stenosis was performed with aortic valve replacement in 106 patients, with mitral valve replacement in 82, and with aortic and mitral valve replacement in 13. There were 143 men and 58 women; the mean age was 67 years. Nine operative deaths (8.5%) occurred with aortic valve replacement and CABG: 5 of 25 (20%) when cardioplegia was not used and 4 of 81 (4.9%) with cardioplegia (p less than 0.01). The operative mortality rate for isolated aortic valve replacement without coronary disease during the same period was 5.9% (10 of 168). The late actuarial survival rate is similar for aortic valve replacement alone or aortic valve replacement and CABG. There were no operative deaths among patients having undergone aortic and mitral valve replacement and CABG; the rate was 15% (9 of 60) in patients having undergone aortic and mitral replacement and CABG. The operative mortality rate was 21.9% for mitral valve replacement and CABG (18 of 82). Rheumatic disease was present in 14 of these patients, two of whom had early deaths (14.3%), both after repeat mitral operations; 11 mitral valve replacements and CABG were done for degenerative mitral regurgitation with no deaths, and the remaining 57 patients had ischemic mitral regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)

Left ventricular systolic performance during upright bicycle exercise in patients with essential hypertension

Left ventricular performance was evaluated at rest and during maximal upright bicycle exercise in 51 patients with chronic essential hypertension. Twenty-eight of these patients had no clinical or electrocardiographic evidence of coronary artery disease and comprise the primary study population. The remaining 23 patients had coronary artery disease and represent a comparison group. First-pass radionuclide angiocardiograms were obtained at rest and during maximal upright bicycle exercise, allowing evaluation of global left ventricular ejection fraction and regional wall motion. At the time of the radionuclide studies, all patients were hypertensive, defined as a diastolic blood pressure 90 mm Hg or greater and/or a systolic blood pressure 140 mm Hg or greater with the patient at rest and sitting. In the primary study group, the left ventricular functional response to upright bicycle exercise was normal in 26 of 28 patients. Left ventricular ejection fraction averaged (+/- standard error) 65 +/- 2 percent at rest and increased significantly to 76 +/- 2 percent with exercise (p less than 0.001). Regional wall motion was normal both at rest and during exercise in all patients. Seventeen patients had electrocardiographic evidence of left ventricular hypertrophy, and 14 were receiving propranolol therapy. The left ventricular functional response also was normal in these subgroups. In contrast to the nearly uniform normal left ventricular responses noted in the patients with hypertension alone, the group with concomitant coronary artery disease had a markedly higher incidence of abnormal left ventricular reserve (19 of 23 versus two of 28, p less than 0.001) during exercise. Thus, in most patients with essential hypertension but without concomitant coronary artery disease, left ventricular reserve during exercise was normal. Hypertension, even with left ventricular hypertrophy, should not be viewed as the cause for an abnormal left ventricular response to exercise in a patient undergoing diagnostic exercise radionuclide angiocardiography.

Electrocardiographic training in primary care residency programs

To evaluate ECT interpretation in physicians training for primary care, we tested residents in two residency programs (one internal medicine, one family medicine) for their ability to interpret ECGs produced in an ambulatory practice. An 18-item examination used abnormal tracings from a university hospital ambulatory unit, including six technical problems generated in the daily operation of the unit. Ability increased with advancing graduate level; however, performance for both internal medicine and family medicine residents fell short of the expected level. Residents completing training in both programs incorrectly interpreted many of the technical problems (eg, limb lead reversal) as well as the usual ECG diagnoses (eg, acute pericarditis). This study suggests that ECG training of primary care residents should be supplemented to meet specific needs of the ambulatory component of primary care practice.

The risk of sudden death in sickle cell trait: noninvasive assessmanet of cardiac response to exercise

The effect of symptom-limited maximal treadmill exercise was evaluated in 34 patients with sickle cell trait (SCT) and 43 controls. Systolic time intervals were measured before and after exercise in 15 of the sickle cell trait subjects, and in 11 controls. Rate pressure product, degree of ST segment depression and incidence of ventricular arrhythmias in subjects with SCT were not significantly different from similar measurements in the control group. No significant difference in electromechanical systole QS2, left ventricular ejection time (LVET), pre-ejection period (PEP)/LVET or ejection fraction (EF) were found between the groups. These data indicate that healthy subjects with SCT do not have an increased incidence of exercise-induced ventricular arrhythmias, myocardial ischemia, or diminished ventricular function compared to normals. Further studies are indicated to elucidate factors that may be operative in sudden death syndrome.

Early thoracotomy for stab wounds of the heart

Fifteen consecutive patients with stab wounds of the heart are reviewed. The left ventricle was stabbed in six patients and right ventricle in four. Sinus tachycardia was present in 54% and hypotension in 67% of cases. Central venous pressure recorded in ten patients was elevated in all but one. Generalized ST segment elevation was the rule among the available preoperative recordings. One patient had right bundle branch block. Thirteen of the fifteen patients had a thoracotomy and two had pericardiocentesis only. Sixty nine percent of the thoracotomies were performed within two hours of the injury. There was only one death of a patient who arrived with no blood pressure or heart sounds. An average follow-up of 20 months revealed long-term sequela of an asymptomatic ventricular aneurysm in one patient. Our unusually gratifying results support the approach of emergency thoracotomy in patients with penetrating cardiac trauma.

Fistulous communication between the left coronary artery and main pulmonary artery: a thirteen-year follow-up

A patient with a fistula producing a 2:1 left-to-right shunt between the coronary arteries and pulmonary artery followed for 13 years is described. The patient remained asymptomatic and without significant electrocardiographic, hemodynamic, or angiographic changes. Large collateral vessels were demonstrated on initial and repeat angiographic studies. This case illustrates the natural history of coronary artery to pulmonary artery shunts and suggests that surgery may not be necessary, even in the presence of a very large communication.

Diagnostic clues in metastatic lesions of endocarditis in addicts

Gram stains and cultures of multiple extravascular sites showed the infecting organisms in 17 of 26 heroin addicts with endocarditis. In addition to routine blood cultures, the etiologic agent was cultured from Osler nodes and Janeway lesions in ten patients, subcutaneous abscesses in eight, pleural fluids in eight, joint aspirates in three, spinal fluids in three, pericardial fluids in two, muscle abscesses in two and endometrium in one patient. Gram-positive cocci were found in extravascular lesions in 11 of 12 patients with staphy-lococcal endocarditis and from as many as four different sites. In contrast, no Gram-positive cocci were seen in extravascular sites in any of eight patients with enterococcal endocarditis although six of them had peripheral lesions. Gram stain and culture of multiple extravascular sites appears to provide a valuable early clue to the nature of the etiologic agent in addict endocarditis.