AIM: To review the direct unfavourable effect of obesity, the most prevalent nutritional and metabolic disease worldwide, on cardiovascular morbidity and mortality. DATA SYNTHESIS: Obesity is associated with high chronic cardiac workload due to the need to supply more blood to peripheral tissue. The high cardiac output is mainly a consequence of the greater requirements of increased lean body mass, and is maintained by an increased stroke volume and high normal heart rate, and sustained by an increase in ventricular mass. The increase in left ventricular (LV) mass also implies an increase in non-muscular tissue that plays a role in the development of electrical abnormalities, heart failure and sudden death. CONCLUSIONS: Obesity per se is a major risk factor for heart failure. Obesity-related LV hypertrophy is in turn associated with varying degrees of systolic and diastolic dysfunction that are not easily recognisable using traditional methods, but are potentially reversible after appropriate, stable moderate weight loss.
