Effects of mental stress on coronary epicardial vasomotion and flow velocity in coronary artery disease: relationship with hemodynamic stress responses

OBJECTIVES

This study examines the prevalence and hemodynamic determinants of mental stress-induced coronary vasoconstriction in patients undergoing diagnostic coronary angiography.

BACKGROUND

Decreased myocardial supply is involved in myocardial ischemia triggered by mental stress, but the determinants of stress-induced coronary constriction and flow velocity responses are not well understood.

METHODS

Coronary vasomotion was assessed in 76 patients (average age 59.9 +/- 10.4 years; eight women). Coronary flow velocity responses were assessed in 20 of the 76 patients using intracoronary Doppler flow. Repeated angiograms were obtained after a baseline control period, a 3-min mental arithmetic task and administration of 200 microg intracoronary nitroglycerin. Arterial blood pressure (BP) and heart rate assessments were made throughout the procedure.

RESULTS

Mental stress resulted in significant BP and heart rate increases (p < 0.001). Coronary constriction (>0.15 mm) was observed in 11 of 59 patients with coronary artery disease (CAD) (18.6%). Higher mental stress pressor responses were associated with more constriction in diseased segments (rdeltaSBP = -0.26, rdeltaDBP = -0.30, rdeltaMAP = -0.29; p's < 0.05) but not with responses in nonstenotic segments. The overall constriction of diseased segments was not significant (p > 0.10), whereas a small but significant constriction occurred in nonstenotic segments (p = 0.04). Coronary flow velocity increased in patients without CAD (32.2%; p = 0.008), but not in patients with CAD (6.4%; p = ns). Cardiovascular risk factors were not predictive of stress-induced vasomotion in patients with CAD.

CONCLUSIONS

Coronary vasoconstriction in angiographically diseased arteries varies with hemodynamic responses to mental arousal. Coronary flow responses are attenuated in CAD patients. Thus, combined increases in cardiac demand and concomitant reduced myocardial blood supply may contribute to myocardial ischemia with mental stress.

Rationale and design of the Prospective Army Coronary Calcium (PACC) Study: utility of electron beam computed tomography as a screening test for coronary artery disease and as an intervention for risk factor modification among young, asymptomatic, active-duty United States Army Personnel

BACKGROUND

Screening for coronary artery calcium with electron beam computed tomography (EBCT) has potential diagnostic and prognostic implications. Most prior research on this technology has been done on selected, high-risk populations. The goal of the Prospective Army Coronary Calcium (PACC) study is to determine the utility of EBCT for the detection of coronary calcium as a screening test for coronary artery disease and as an intervention for risk factor modification among young, asymptomatic, active-duty personnel undergoing the United States Army's Cardiovascular Screening Program.

METHODS AND RESULTS

Three study designs will be used to address the objectives of this investigation: (1) a cross-sectional study of 2000 unselected, consecutive participants to determine the prevalence and extent of coronary calcification in the 40- to 45-year-old Army population, (2) a randomized, controlled trial with a 2 x 2 factorial design involving 1000 participants to assess the impact of EBCT information on several dimensions of patient behavior, with and without intensive risk factor case management, and (3) a prospective cohort study of 2000 participants followed for at least 5 years to establish the relation between coronary calcification and cardiovascular events in an unselected, "low-risk" (by conventional standards) Army population.

CONCLUSIONS

We present a review of the literature on the clinical utility of EBCT, with a focus on the limited research in young, asymptomatic populations. The details of the PACC study (begun in October1998) are presented. The results of the PACC study will determine the clinical utility of EBCT in young, asymptomatic patients.

Nongenital pelvic leiomyosarcoma metastatic to the heart

A patient who had a 5-year history of a low-grade nongenital pelvic leiomyosarcoma was evaluated for worsening dyspnea, hypertension, and jugular venous distension. An echocardiogram revealed a large right atrial mass. At surgical exploration, metastatic leiomyosarcoma was found within the inferior vena cava extending from below the renal veins up into the right atrium. Using cardiopulmonary bypass with profound hypothermia and circulatory arrest, the inferior vena cava was opened below the renal veins, and the tumor was transected. That portion of the tumor above this transection was then extracted through a right atriotomy. Resection of the pelvic tumor was not thought to be feasible. The patient remains asymptomatic with stable pelvic tumor 1 year after the procedure.