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To evaluate the effects of age and pulmonary hypertension on phasic right atrial function we measured right atrial volumes at 3 different points in the cardiac cycle in 57 healthy subjects and 33 patients with pulmonary arterial hypertension. Right atrial reservoir function was assessed by systolic filling volume and passive and active emptying by passive and active emptying volume and fraction of total emptying. We compared these phases of right atrial function in 30 healthy subjects

Paravalvular jets, documented by intraoperative transesophageal echocardiography, have prompted immediate valve explantation by others, yet the significance of these jets is unknown.Twenty-seven patients had intraoperative transesophageal two-dimensional color Doppler echocardiography, performed to assess the number and area of regurgitant jets after valve replacement, before and after protamine. Patients were grouped by first time versus redo operation, valve position and type.Before protamine, 55 jets were identified (2.04+/-1.4 per patient) versus 29 jets after (1.07+/-1.2 per patient, p = 0.0002). Total jet area improved from 2.0+/-2.2 cm2 to 0.86+/-1.7 cm2 with protamine (p0.0001). In all patients jet area decreased (average decrease, 70.7%+/-27.0%). First time and redo operations had similar improvements in jet number and area (both p0.6). Furthermore, mitral and mechanical valves each had more jets and overall greater jet area when compared to aortic and tissue valves, respectively.Following valve replacement, multiple jets are detected by intraoperative transesophageal echocardiography. They are more common and larger in the mitral position and with mechanical valves. Improvement occurs with reversal of anticoagulation.

We assessed the effects of implantation of Myosplint (Myocor, Maple Grove, Minn), a device that changes left ventricular (LV) cross-sectional shape from circular to bilobar, on regional LV function. A total of 10 open-chest dogs with tachycardia-induced cardiomyopathy were studied before and after Myosplint implantation. LV cross-sectional epicardial echocardiography at the papillary muscle level was performed along with acquisition of hemodynamic data. LV normalized thickening, fractional thickening, end-diastolic thickness, and end-diastolic curvatures were calculated for 10 LV segments. Myosplint implantation did not affect LV hemodynamics, but decreased average end-diastolic curvature (P.0001) and increased its segmental heterogeneity (P.0001). There was no change in average fractional thickening, whereas normalized thickening increased (P =.05). In contrast, segmental heterogeneity of both normalized and fractional thickening increased (P =.02 and P =.01, respectively). Structural modeling confirmed that Myosplint implantation increases regional stress heterogeneity and curvature heterogeneity. LV cross-sectional shape markedly affects regional LV performance.

A 22-year-old man who had hypertrophic cardiomyopathy and progressive exertional dyspnea despite treatment with β-blockers was referred for septal myectomy. Preoperative transthoracic echocardiography showed severe asymmetric septal hypertrophy (septal thickness of 3.1 cm) with marked systolic anterior motion of the mitral valve and a dynamic left ventricular outflow tract (LVOT) gradient of 125 mm Hg. Epicardial real-time 3-dimensional echocardiography (RT3DE) (Sonos 7500, Philips Medical Systems), was performed intraoperatively, providing …

Recently, 3D echocardiography (3DE) has developed the capability to capture 3D images in real-time and has been reported to be accurate for estimating left ventricular (LV) volume. The authors hypothesized that real-time 3DE could determine LV stroke volumes (SV) more accurately than conventional 2DE. The aim of this study was to compare 2DE and 3DE for estimating LV stroke volumes during a variety of hemodynamic conditions, including left anterior descending (LAD) coronary artery occlusions. During a total of 30 hemodynamic conditions in 6 sheep with chronic aortic regurgitation, electromagnetic (EM) flow probes and meters were used to obtain LV SV. LV end-diastolic (LV EDV) and LV end-systolic volumes (LV ESV) were measured using real-time; 3DE with Simpson's rule (slice spacing 7 mm). For 24 conditions without LAD occlusions, SV by EM ranged from 27 to 66 ml (average 45/spl plusmn/10 ml). The correlation for LV SV measured by 3DE and that by EM was excellent (r=0.92, y=0.91x+3.6, /spl Delta/=-1/spl plusmn/4 ml, n=24), and better than that between 2DE and EM (r=0.62, y=0.68x+8.8, /spl Delta/=-5.6/spl plusmn/9.4 ml, p=0.0003). For 6 conditions during LAD occlusion, SV by EM ranged from 26 to 58 ml (average 41/spl plusmn/12 ml). SV derived from 3DE also agreed well with values derived by EM (r=0.96); however, the r-value between 2DE and EM was reduced to 0.58. It is concluded that real-time 3DE provided accurate assessment of LV SV under both ischemic and nonischemic conditions, while conventional 2DE showed poor correlations with reference standards, especially for SVs during coronary artery occlusion.

To evaluate the load dependence of effective regurgitant orifice area (ROA) in an animal model of chronic aortic regurgitation.Eight sheep were studied 10-20 weeks after the surgical creation of aortic regurgitation. After baseline studies, 500 ml of blood, angiotensin II, and nitroprusside were infused sequentially. Electromagnetic flow meters were used as reference standards to determine aortic regurgitation volume. The time-velocity integral was acquired using the continuous wave Doppler method.Baseline aortic regurgitant volume varied from 8 ml (regurgitant fraction 28%) to 29 ml (59%), with a mean (SD) value of 17 (8) ml; mean ROA was 0.15 (0.05) cm2. During angiotensin II infusion, aortic regurgitation volume (20 (8) ml) and mean diastolic aortoventricular pressure gradient (62 (18) mm Hg) increased by 26 (16)% and 48 (64)%, respectively (p0.01 for both). ROA did not change (0.16 (0.06) cm(2), p = 0.15). During nitroprusside infusion, aortic regurgitant volume (13 (7) ml, p = 0.05) and diastolic pressure gradient (25 (13) mm Hg, p0.05) decreased. ROA did not change (0.15 (0.05) cm2). When analysing 32 stages together, aortic regurgitant volume (r = 0.78, p0.01) and regurgitant fraction (r = 0.55, p0.01) correlated well with ROA. However, diastolic pressure gradient (r = 0.28) was not significantly correlated with ROA.In an animal model of chronic aortic regurgitation, ROA did not change with load alterations.

Background . The Cosgrove-Edwards Annuloplasty System includes a universally flexible band that corrects mitral annular dilatation via measured plication of the posterior annulus. The purpose of this study was to evaluate midterm clinical and functional results in the first 197 patients receiving this flexible annuloplasty band at mitral valve repair. Methods . From February 1993 to July 1994, 197 consecutive patients with mitral regurgitation had mitral valve repair using this system. Valve disease was degenerative in 73%, rheumatic in 15%, ischemic in 5%, infectious in 2.5%, and other in 4%. Results . Immediately after repair, echocardiographic mitral regurgitation was none or trivial in 92%, 1+ in 5%, and 2+ in 3%. There were no hospital deaths. Late follow-up was available in 195 patients (99%), with 661 patient-years of follow-up available for analysis. Four-year actuarial survival was 93%, freedom from thromboembolism 94%, from endocarditis 98%, and from reoperation 95%. At a mean interval of 18 months, echocardiography in 157 patients demonstrated no or trace mitral regurgitation in 56%, 1+ in 24%, 2+ in 9%, 3+ in 6%, and 4+ in 3%. At a mean of 61 ± 5 months, reconstruction of the mitral annulus from real-time three-dimensional echocardiographic images in 10 patients confirmed preserved nonplanar shape and sphincter mechanism of the mitral annulus. Annular orifice area decreased 28% ± 11% during the cardiac cycle from a mean of 10.1 ± 3.9 cm 2 in diastole to 7.2 ± 2.8 cm 2 in systole. Conclusions . This annuloplasty system is effective for repair of mitral regurgitation secondary to all causes and preserves mitral annular flexibility and function at 5-year follow-up.