Epidemiology, Etiology, and Natural History of Tricuspid Regurgitation

Epidemiology

Using echocardiography, the Framingham Heart study investigators found a prevalence of moderate or severe TR of 0.8% and an increased prevalence with aging. In 2000, the worldwide population of persons aged older than 65 years was an estimated to be 420 million. From 2000 to 2030, the worldwide population aged older than 65 years is projected to increase by approximately 550 million to 973 million, increasing from 6.9% to 12.0% worldwide, from 15.5% to 24.3% in Europe, from 12.6% to 20.3% in North America, from 6.0% to 12.0% in Asia, and from 5.5% to 11.6% in Latin America and the Caribbean. The largest increases in absolute numbers of older persons will occur in developing countries. From 2000 to 2030, the number of persons in developing countries aged older than 65 years is projected to almost triple, from approximately 249 million in 2000 to an estimated 690 million in 2030, and the developing countries’ share of the world’s population aged older than 65 years is projected to increase from 59% to 71%. Thus, the already notable prevalence of significant TR will most likely increase dramatically in the near future.

Overall, the prevalence of significant TR was 4.3 times greater in women than in men. Recently, in a retrospective, observational study including 16,380 echocardiograms performed at Mayo Clinic over a 10-year interval, Topilsky and coworkers found that the prevalence of isolated TR of moderate or greater severity among the inhabitants of the Olmsted County was 0.4%, seen more commonly in women and elderly persons. Moderate or severe TR accompanied around 25% of all left-side heart valve diseases. The most common cause of moderate or severe TR in community residents diagnosed by Doppler echocardiography was functional TR secondary to left valvular disease (49.5%) followed by functional TR associated with pulmonary hypertension unrelated to any heart disease (23.0%), functional TR related to left ventricular dysfunction (12.9%), functional isolated TR (8.1%), organic TR (4.8%), and congenital (1.7%). When the severity of isolated TR was moderate or greater, survival was worse than for matched control participants with trivial or less TR. Notably, atrial fibrillation is increasingly more recognized as an important factor in the cause of functional TR, and its prevalence in the so-called “isolated functional TR” group of the Olmsted county study was 68%.

TR is frequently present in patients with mitral valve disease, and more than one-third of patients with mitral stenosis have at least moderate.TR Severe TR has been reported in 23% to 37% of patients after mitral valve replacement for rheumatic valve disease. In the majority of patients, TR is not related to primary valve pathology and is defined as “functional.” Functional TR is frequently observed in the advanced stage of left-sided valvular heart disease or myocardial disease. ^,

In 14% of patients, TR may occur in the absence of structural tricuspid valve alterations, pulmonary hypertension, or left heart dysfunction. ^,

Finally, the development of hemodynamically significant TR has been reported in 27% of patients who had only mild TR at the time of left-sided valve surgery. In most cases, TR is diagnosed late after mitral valve replacement. ^,