Right ventricular performance in patients with coronary artery disease

While left ventricular (LV) performance in patients with coronary artery disease (CAD) has been extensively investigated, little attention has been given to right ventricular (RV) function in this disease. For this purpose, a new geometric model for RV volume was developed and RV end diastolic volume index (EDVI), end systolic volume index (ESVI), stroke volume index (SV1) and ejection fraction (EF) were determined from biplane RV cineangiograms in 26 patients. Eight patients served as normal (control) subjects (group I). 18 patients with obstructive CAD comprised two other groups: six who had no significant disease of the right coronary artery (RCA) (group II) and 12 who had a high grade RCA lesion (group III). The mean values for EDVI, SVI and EF in group I were 76 ± 11 ml/m², 50 ± 6 ml/m², and 66 ± 6%. The only significant difference between groups I and II was that SVI was lower in group II than in group I (P < 0.01). No measurements in groups II and III were statistically different from each other. However, markedly subnormal values were found in group III (EDVI: 61 ± 16 ml/m², SVI: 33 ± 10 ml/m² and EF: 52 ± 7%); all values being significantly lower (SVI and EF: P < 0.001; EDVI: P < 0.05) than in group I, RV end diastolic pressure was normal in all patients. These findings may be related to reduced RV compliance, distorted LV geometry, possible RV ischemia or reduced Frank Starling effect.