Cardiac Rehab in the Quest for a Happier and Healthier Heart

Over the course of the millennia, cultures from around the world independently came to the same erroneous conclusion that emotions originate in the heart. Indeed, the words anger, angst, anguish, and angina all derived from the same Greek root word meaning constriction. Though emotions emanate from the brain, they resonate powerfully and almost instantaneously with the heart and cardiovascular (CV) system. A growing body of data indicates that a happy and socially connected heart is generally healthier than a heart burdened by depression, loneliness, anger, or anxiety.

A recent large multinational study reported that psychosocial stress accounted for approximately 30% of the population's attributable risk for acute myocardial infarction, placing it behind only lipids and smoking in importance among the 9 major modifiable coronary artery disease (CAD) risk factors.¹ Pathologic depression, social isolation, cynical distrust, hostility, pessimism, and a sense of hopelessness have each been linked to adverse CV events.^2-4 Spikes in the incidence of cardiac deaths, lethal arrhythmias, and myocardial infarctions have been documented in the affected populations immediately after anxiety-provoking disasters such as earthquakes² and 9/11 terrorist attacks. In contrast, factors that have been associated with improved psychosocial stress and lower rates of CV mortality and morbidity include social connection, exercise, optimism, humor, altruism, animal companionship, and involvement in organized religion.²

Psychosocial stressors are believed to increase CV risk by activating the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis, resulting in sympathetic predominance and increased cortisol levels, respectively.^3,4 Excess stress can adversely affect blood pressure, blood glucose, and lipid levels, and can also increase atherosclerosis progression, inflammation,⁵ and predispose stressed persons to endothelial dysfunction and central obesity.⁶

Yet multiple problems need to be addressed before this knowledge can be clinically applied. A scientific consensus does not exist regarding the optimal tool for quantifying psychosocial stress. In addition, the ideal approach to lowering psychological distress and improving stress-related adverse prognoses is unclear. Pharmacologic therapy is the standard approach to stress reduction; and although antidepressants improve symptoms of depression in CAD patients,⁷ they have not been shown to favorably alter the CV prognosis.⁸ Beta adrenergic blocking agents reduce excess sympathetic tone that is characteristically present in sad, angry, or anxious CAD patients; and although these agents improve both atherosclerosis progression and CV events; they can cause or aggravate depression.⁹

The recent study by Artham et al¹⁰ addresses stress-related CV toxicity in a practical fashion by using the Kellner system questionnaire to quantify psychosocial distress among patients with CAD, and then implementing a cardiac rehabilitation and exercise training program (CRET) in an attempt to treat the stress.¹⁰ This study showed that the CRET resulted in a 50% improvement in exercise capacity with nearly 50% reductions in scores for anxiety and depression in the high distress patient.¹⁰ Participation in CRET has been shown in multiple studies to significantly improve CV morbidity and mortality by 20% to 50%. To what extent these benefits are due to improvements in psychosocial stress rather than gains in fitness and CV risk factors remains unclear. Nonetheless, regular physical activity and a social support group, both of which are provided by CRET, improve mood,¹¹ anxiety, fitness, CV risk factors, and prognosis.

In summary, psychosocial stress is common both as a cause and a complication of symptomatic coronary disease. A prescription for a structured exercise program, especially CRET, would seem to be a logical, practical, and now proven aid in the healing process for stressed CAD patients, supporting them in the quest for a happier and healthier heart.