Elsa Grace V Giardina

Premature Atrial Stimulation as a Key to the Understanding of Sinoatrial Conduction in Man: Presentation of Data and Critical Review of the Literature

Since recording potentials directly from the sinoatrial node (SAN) is not yet possible, the electrophysiologic evaluation of this structure in intact human subjects must be accomplished with indirect technics. Two technics have been used to study SAN function in man: premature atrial stimulation (PAS) and rapid atrial pacing. Recent discussions of data using these technics have emphasized their role in determining SAN automaticity, but their role in evaluating conduction from atrium to SAN or SAN to atrium has not been fully explored. Using the technic of PAS, we have studied five patients with sinus bradycardia and symptoms of dizziness or syncope. Our analysis of the results obtained from these studies discloses the unique ability of this technic to evaluate conduction into and out of the SAN. An atrial premature depolarization (APD) elicited late in atrial diastole is followed by a compensatory pause (nonreset of the SAN pacemaker). An APD elicited earlier in atrial diastole is followed by a pause that is less than compensatory (SAN reset). From these responses estimates of sinoatrial conduction time were made. In one patient reset was never seen, suggesting markedly prolonged sinoatrial conduction. With these results in mind, the literature was reviewed and an alternate interpretation posed for existing data. PAS is not only a means of determining SAN automaticity, but also a very useful means of unmasking sinoatrial conduction abnormalities.

Metabolic Syndrome and Ischemic Stroke Risk Northern Manhattan Study

Background and Purpose— More than 47 million individuals in the United States meet the criteria for the metabolic syndrome. The relation between the metabolic syndrome and stroke risk in multiethnic populations has not been well characterized. Methods— As part of the Northern Manhattan Study, 3298 stroke-free community residents were prospectively followed up for a mean of 6.4 years. The metabolic syndrome was defined according to guidelines established by the National Cholesterol Education Program Adult Treatment Panel III. Cox proportional-hazards models were used to calculate hazard ratios (HRs) and 95% CIs for ischemic stroke and vascular events (ischemic stroke, myocardial infarction, or vascular death). The etiologic fraction estimates the proportion of events attributable to the metabolic syndrome. Results— More than 44% of the cohort had the metabolic syndrome (48% of women vs 38% of men, P<0.0001), which was more prevalent among Hispanics (50%) than whites (39%) or blacks (37%). The metabolic syndrome was associated with increased risk of stroke (HR=1.5; 95% CI, 1.1 to 2.2) and vascular events (HR=1.6; 95% CI, 1.3 to 2.0) after adjustment for sociodemographic and risk factors. The effect of the metabolic syndrome on stroke risk was greater among women (HR=2.0; 95% CI, 1.3 to 3.1) than men (HR=1.1; 95% CI, 0.6 to 1.9) and among Hispanics (HR=2.0; 95% CI, 1.2 to 3.4) compared with blacks and whites. The etiologic fraction estimates suggest that elimination of the metabolic syndrome would result in a 19% reduction in overall stroke, a 30% reduction of stroke in women; and a 35% reduction of stroke among Hispanics. Conclusions— The metabolic syndrome is an important risk factor for ischemic stroke, with differential effects by sex and race/ethnicity.

Racial/Ethnic Disparities in Time to Follow-Up after an Abnormal Mammogram

BACKGROUND Although non-Hispanic white women have an increased risk of developing breast cancer, the disease-specific survival is lower for African American and Hispanic women. Little is known about disparities in follow-up after an abnormal mammogram. The goal of this study was to investigate potential disparities in follow-up after an abnormal mammogram. METHODS A retrospective cohort study of 6722 women with an abnormal mammogram and documented follow-up from January 2000 through December 2002 was performed at an academic medical center in New York City. The outcome was the number of days between the abnormal mammogram and follow-up imaging or biopsy. Cox proportional hazards models were used to assess the effect of race/ethnicity and other potential covariates. RESULTS The median number of days to diagnostic follow-up after an abnormal mammogram was greater for African American (20 days) and Hispanic (21 days) women compared with non-Hispanic white (14 days) women (p < 0.001). Racial/ethnic disparities remained significant in a multivariable model controlling for age, Breast Imaging Reporting and Data System (BIRADS) category, insurance status, provider practice location, and median household income. CONCLUSIONS After an abnormal mammogram, African American and Hispanic women had longer times to diagnostic follow-up compared with non-Hispanic white women. Future efforts will focus on identifying the barriers to follow-up so that effective interventions may be implemented.

Effect of imipramine and nortriptyline on left ventricular function and blood pressure in patients treated for arrhythmias

The effect of imipramine or nortriptyline on left ventricular function and orthostatic blood pressure was evaluated in 20 nondepressed cardiac patients treated for ventricular premature depolarizations (VPDs). Drug was administered by mouth and dose ranging used, 1 mg/kg/day (imipramine) or 0.5 mg/kg/day (nortriptyline), was increased after four doses (imipramine) or six doses (nortriptyline) until greater than 80% suppression of VPDs or adverse effects occurred or until a maximum dose of 5 mg/kg/day (imipramine) or 3.5 mg/kg/day (nortriptyline) was given. Fourteen (70%) had greater than 80% VPD suppression, five had less than 80% improvement (range 25% to 77%), and one had a VPD frequency increase of 6%. Mean daily imipramine dose was 210 +/- 103 mg and mean nortriptyline dose was 100 +/- 29 mg. Neither drug significantly changed mean ejection fraction or peak systolic pressure end-systolic volume ratio by radionuclide angiogram. Both reduced standing systolic blood pressure: mean change after imipramine was 26 mm Hg (NS), and after nortriptyline, 14 mm Hg (p less than 0.05). Drug was discontinued in two patients because of symptomatic orthostatic blood pressure change greater than 30 mm Hg. There was not a significant relationship between dose, drug concentration, or functional class and orthostatic change in systolic blood pressure but there was for age (p less than 0.05). These observations suggest that even cardiac patients with impaired systolic function may take imipramine or nortriptyline for VPDs; however, frequent blood pressure measurement is advised, particularly in older patients.

The DHHS Office on Women's Health Initiative to Improve Women's Heart Health: Focus on Knowledge and Awareness Among Women with Cardiometabolic Risk Factors

UNLABELLED Abstract Background: The diversity of the U.S. population and disparities in the burden of cardiovascular disease (CVD) require that public health education strategies must target women and racial/ethnic minority groups to reduce their CVD risk factors, particularly in high-risk communities, such as women with the metabolic syndrome (MS). METHODS The data reported here were based on a cross-sectional face-to-face survey of women recruited from four participating sites as part of the national intervention program, Improving, Enhancing and Evaluating Outcomes of Comprehensive Heart Care in High-Risk Women. Measures included baseline characteristics, sociodemographics, CVD related-knowledge and awareness, and Framingham risk score (FRS). RESULTS There were 443 of 698 women (63.5%) with one or more risk factors for the MS: non-Hispanic white (NHW), 51.5%; non-Hispanic black (NHB), 21.0%; Hispanic, 22.6%. Greater frequencies of MS occurred among Hispanic women (p<0.0001), those with less than a high school education (70.0%) (p<0.0001), Medicaid recipients (57.8%) (p<0.0001), and urbanites (43.3%) (p<0.001). Fewer participants with MS (62.6%) knew the leading cause of death compared to those without MS (72.1%) (p<0.0001). MS was associated with a lack of knowledge of the composite of knowing the symptoms of a heart attack plus the need to call 911 (odds ratio [OR] 0.41, 95% confidence interval [CI] 0.17-0.97, p=0.04). CONCLUSIONS Current strategies to decrease CVD risk are built on educating the public about traditional factors, including hypertension, smoking, and elevated low-density lipoprotein cholesterol (LDL-C). An opportunity to broaden the scope for risk reduction among women with cardiometabolic risk derives from the observation that women with the MS have lower knowledge about CVD as the leading cause of death, the symptoms of a heart attack, and the ideal option for managing a CVD emergency.

Physical activity participation among Caribbean Hispanic women living in New York: relation to education, income, and age.

BACKGROUND Inadequate participation in physical activity is a serious public health issue in the United States, with significant disparities among population groups. In particular, there is a scarcity of information about physical activity among Caribbean Hispanics, a group on the rise. METHODS Our goal was to accumulate data on physical activity among Caribbean Hispanic women living in New York and determine the relation between physical activity and age, marital status, education, income, primary language, and children in the household. To this end, a survey adapted from the National Health Interview Survey of the National Center for Health Statistics assessing type, frequency, and duration of physical activity was administered. RESULTS There were 318 self-identified Hispanic women who participated. Total activity time, mean 385 +/- 26 minutes, and education (r = 0.14, p < 0.01) were significantly related. Women who had attended some college had greater total activity time than those with some high school education (p = 0.046) or < 8th grade education (p = 0.022). Walking as a form of transportation was the most frequent pursuit, 285 +/- 21 minutes. Age (r = -0.34, p < 0.001) and education (r = 0.25, p < 0.001) correlated with nonwalking activity time (leisure time). Nonwalking activity times were greater in younger, that is, 18-29 years (p < 0.001) and college-educated women (p < 0.001). Physical activity recommendations were met by 11%; and 17% reported no physical activity. CONCLUSIONS Among Caribbean Hispanic women living in New York City, the current recommendations for physical activity are met by 11%, and physical activity and education are significantly related. Our observation that education is a critical factor related to physical activity suggests that programs to address the promotion of a physically active lifestyle are needed.

Time course of alpha-1-acid glycoprotein and its relation to myocardial enzymes after acute myocardial infarction.

The acute phase reactant, alpha-1-acid glycoprotein, binds to a number of basic antiarrhythmic drugs, including lidocaine, quinidine, propranolol, imipramine and disopyramide. Binding to alpha-1-acid glycoprotein accounts for a decrease in free drug fraction and may alter the expected concentration: response relation of drugs particularly when there are unpredictably large or rapid changes in alpha-1-acid glycoprotein. To determine the time course and magnitude of alpha-1-acid glycoprotein for 1 month after acute myocardial infarction (AMI), blood samples were collected from 27 patients, 14 with AMI and 13 with a chest pain syndrome but no AMI. Patients with AMI had a significant increase in alpha-1-acid glycoprotein after 72 hours (mean 153 +/- 35 mg/dl) (p less than 0.05), and the maximum was observed on day 7 (mean 165 +/- 53 mg/dl) (p less than 0.05), returning to baseline by 28 days. There was no significant change in alpha-1-acid glycoprotein in patients with chest pain but no AMI. Regression analysis showed a significant relation between creatine kinase (p less than 0.005) and lactic dehydrogenase (p less than 0.001) vs alpha-1-acid glycoprotein indicating alpha-1-acid glycoprotein concentration is high in patients with large AMI. Changes in binding resulting from alpha-1-acid glycoprotein during AMI could account for misinterpretation of total drug concentration and response to antiarrhythmic drugs acutely, during convalescence and at discharge.

The Office on Women's Health Initiative to Improve Women's Heart Health: Program Description, Site Characteristics, and Lessons Learned

AIMS Improving, Enhancing and Evaluating Outcomes of Comprehensive Heart Health Care Programs for High Risk Women has funded six diverse centers to provide chronic disease risk factor screening and lifestyle interventions for women and focuses specifically on low-income, minority women. RESULTS This article describes the rationale for these diverse programs across the country, all focusing on improving outcomes for women with or at risk for cardiovascular disease (CVD). The six programs include College of Physicians and Surgeons at Columbia University, Christ Community Health Services in Memphis, Womens Heart Center of Fox Valley Cardiovascular Consultants, University of Minnesota, University of California Davis Womens Cardiovascular Medicine Program, and Yale-New Haven Hospitals Womens Heart Advantage. CONCLUSIONS We present six differing approaches to womens heart programs. Based on this experience, promoting CVD prevention in women is a feasible healthcare delivery strategy for health promotion and for delivering preventive strategies for high-risk women. It is possible to deliver heart-healthy programs through existing healthcare infrastructures. These programs provide important models for public health, voluntary, and other health organizations to develop networks for population-based, targeted, relatively low cost programs that support Healthy People 2010 objectives for lifestyle changes and cardiovascular health. Ongoing longitudinal analysis of the programs will provide information about clinical outcomes and sustainability of such programs beyond the funding period.

The implications of left ventricular performance for tricyclic antidepressant drug treatment

Early animal work with the tricyclic antidepressants indicated that these drugs are cardiotoxic and, more specifically, that they adversely affect cardiac contractility. This has been a consistent finding across a large number of clinical studies looking at a variety of tricyclic drugs in a variety of test animals (Kaumann et al., 1965; Laddu and Somani, 1969; Langslet et al., 1971). However, as is so commonly the problem with such data, these studies implied, but in no way could definitively establish, what these drugs would do in humans. An uncertainty remained because of the difficulty in interpreting concentration and metabolic differences between man and various experimental animals. During the 1960s a number of investigators reported cases of tricyclic overdose where myocardial failure was a major clinical problem (Laddu and Somani, 1969; Sigg et al., 1963). These reports cite the animal data as evidence to explain the clinical symptomatology of these patients and then concluded that the clinical symptomatology of these patients was prima facie evidence for the existence of a direct negative inotropic effect from tricyclic drugs. Unfortunately, these reports did not include direct measurements of left ventricular performance.