n adults, tricuspid regurgitation (TR) usually occurs secondary to left-sided valvular lesions or chronic pulmonary disease. Secondary TR, in conjunction with left-sided valve disease and left ventricular (LV) dysfunction, even with a structurally normal tricuspid valve (TV), is thought to be caused by tricuspid annular dilatation 1 and tethering of the TV leaflet after right ventricular (RV) dilatation. In contrast to secondary TR, acquired isolated TR can be defined when TR is present without other valvular lesions, pulmonary disease or pulmonary hypertension. 2,3 Because of the paucity of data, management and clinical decision-making regarding patients with isolated TR is difficult. Furthermore, the mechanism of isolated TR remains unknown. We hypothesize that RV remodeling and dysfunction would be the most important mechanism for isolated TR. Therefore, we evaluated RV function and TV deformities (TV annular dilatation and tethering) in patients with isolated TR and compared these parameters with ageand gender-matched patients with secondary TR, as well as
MethodsWe reviewed approximately 20,000 patients who had echocardiograms in our laboratory over a 5-year period retrospectively. Patients with secondary TR associated with significant other valvular disease, LV systolic dysfunction, coronary artery disease and a RV systolic pressure greater than 50 mmHg were excluded. We also excluded the patients with Ebstein's anomaly and thyroid dysfunction.TR was graded qualitatively by Framingham Heart Study criteria: 4 mild if the regurgitant jet area/right atrial area was 19% or less; moderate if 20% to 40%; or severe if ≥41%. Enlargement of the RV was considered mild if the RV was greater than two-thirds of the LV but less than the LV size; moderate if the RV equaled the LV; and severe if the RV was greater than the LV at apical 4-chamber view. 5 The peak TR velocity was measured by continuous-wave Doppler, and pulmonary arterial systolic pressure was estimated by measurement of the systolic regurgitant tricuspid flow velocity and an estimate of right atrial pressure (RAP) applied in the modified Bernoulli method: RVSP = 4V 2 + RAP. 6,7 RAP is estimated value from characteristics of the inferior vena cava with respiratory variation. 8 Twelve patients were diagnosed as isolated severe TR. We also selected the age-and gender-matched patients with secondary TR associated with pulmonary hypertension and control participants for comparison of echocardiographic parameters with isolated TR patients. Among patients with
Right Ventricular Remodeling and Dysfunction With Subsequent Annular Dilatation and Tethering as a Mechanism of Isolated Tricuspid RegurgitationHye-Sun Seo, MD, PhD; Jong-Won Ha, MD, PhD; Jae Youn Moon, MD; Eui-Young Choi, MD, PhD; Se-Joong Rim, MD, PhD; Yangsoo Jang, MD, PhD; Namsik Chung, MD, PhD; Won-Heum Shim, MD, PhD; Seung-Yun Cho, MD, PhD; Sung Soon Kim, MD, PhDBackground Secondary tricuspid regurgitation (TR) as a result of pulmonary hypertension and/or left-sided heart disease is caused by tricus...
