Gender-related differences in patients undergoing mechanical aortic valve replacement with the CarboMedics valve.

AIM: The aim of this paper was to evaluate gender-related differences in patients undergoing mechanical aortic valve replacement with the CarboMedics valve. METHODS: During a 20 year period, 629 patients (median age 60 years) underwent mechanical aortic valve replacement with the CarboMedics valve. Of these, 215 patients were female (34%). The median follow-up for the entire cohort was 10.2 ± 6.2 years. RESULTS: In-hospital mortality for the entire cohort was 9% (male 7.3% vs. female 11.0%, P=0.005). Cox regression analysis revealed redo-surgery (HR=2.35, CI 1.35-4.08), LVEF<30% (HR=2.31, CI 1.36-3.93), age (HR=1.60, CI 1.27-2.02), as well as female gender (HR=2.07, CI 1.28-3.35) as independent predictors of survival. For male gender LVEF<30% (HR=2.47, CI 1.23-4.93) and age (HR=1.75, CI 1.25-2.43) were independent predictors of survival. For female gender, additional CABG (HR=2.15, CI 1.08-4.28), redo surgery (HR=3.64, CI 1.78-7.46) as well as age (HR=1.48, CI 1.06-2.06) were independent predictors of survival. CONCLUSION: Gender per se is an independent risk factor of survival after mechanical aortic valve replacement. Severely impaired LVEF independently predicts survival in males whereas additional CABG and redo surgery do in females. Age affects survival in both sexes. These findings may serve as a basis for further improving gender related outcome.

Loss of high-molecular-weight von Willebrand factor multimers mainly affects platelet aggregation in patients with aortic stenosis.

Severe aortic stenosis is associated with a haemostatic abnormality that resembles acquired von Willebrand syndrome type 2. It is assumed that high shear conditions render large von Willebrand factor (VWF) multimers accessible to cleavage by ADAMTS-13. However, whether loss of these large multimers affects platelet function by impairing adhesion, aggregate formation, or both has not been evaluated in clinical studies. We prospectively enrolled 47 patients with severe aortic stenosis, and studied them prior to aortic valve surgery and at a median of six months after valve replacement. We investigated levels of large VWF multimers, platelet function under high shear conditions, and residual response to suboptimal concentrations of ADP to express P-selectin. As expected, there was a significant reduction of VWF large multimers before surgery that resolved thereafter in most patients (p<0.0001). The closure time of the ADP cartridge of the PFA-100 was also corrected in most patients after the operation (p<0.0001). We used the cone and plate(let) analyser Impact-R to differentiate between adhesion and aggregation. Both adhesion (p=0.03) and ADP-inducible platelet aggregation (p=0.002) improved considerably after valve replacement. Consequently, ADP-inducible expression of P-selectin was higher after valve replacement (p=0.001). We conclude that reduced levels of large VWF multimers associated with aortic stenosis lead to impairment of both adhesion and, especially, ADP-inducible platelet aggregation.

Moderate patient-prosthesis mismatch after valve replacement for severe aortic stenosis has no impact on short-term and long-term mortality.

BACKGROUND: The importance of moderate patient-prosthesis mismatch (PPM) for the prognosis of patients who undergo aortic valve replacement is unclear. METHODS: The presence of PPM was assessed in 361 consecutive patients undergoing valve replacement for isolated severe aortic stenosis and related to perioperative and postoperative mortality. Indexed effective orifice areas (EOAi) were estimated for each type and size of prosthesis. RESULTS: Using the previously proposed cut-off of EOAi

[Identification of high risk patients with severe, but asymptomatic aortic stenosis]. / Identifizierung von Hochrisikopatienten bei schwerer, aber symptomfreier Aortenstenose.

Whether asymptomatic patients with severe aortic stenosis benefit from surgery remains unclear. We report our data recently published in the New England Journal of Medicine on the natural history of this disease and predictors of outcome.

Improved assessment of mitral valve stenosis by volumetric real-time three-dimensional echocardiography.

OBJECTIVES: This study was performed to determine the feasibility, accuracy and reproducibility of real-time volumetric three-dimensional echocardiography (3-D echo) for the estimation of mitral valve area in patients with mitral valve stenosis. BACKGROUND: Planimetry of the mitral valve area (MVA) by two-dimensional echocardiography (2-D echo) requires a favorable parasternal acoustic window and depends on operator skill. Transthoracic volumetric 3-D echo allows reconstruction of multiple 2-D planes in any desired orientation and is not limited to parasternal acquisition, and could thus enhance the accuracy and feasibility of calculating MVA. METHODS: In 48 patients with mitral stenosis (40 women; mean age 61 +/- 13 years) MVA was determined by planimetry using volumetric 3-D echo and compared with measurements obtained by 2-D echo and Doppler pressure half-time (PHT). All measurements were performed by two independent observers. Volumetric data were acquired from an apical view. RESULTS: Although 2-D echo allowed planimetry of the mitral valve in 43 of 48 patients (89%), calculation of the MVA was possible in all patients when 3-D echo was used. Mitral valve area by 3-D echo correlated well with MVA by 2-D echo (r = 0.93, mean difference, 0.09 +/- 0.14 cm2) and by PHT (r = 0.87, mean difference, 0.16 +/- 0.19 cm2). Interobserver variability was significantly less for 3-D echo than for 2-D echo (SD 0.08cm2 versus SD 0.23cm2, p < 0.001). Furthermore, it was much easier and faster to define the image plane with the smallest orifice area when 3-D echo was used. CONCLUSIONS: Transthoracic real-time volumetric 3-D echo provides accurate and highly reproducible measurements of mitral valve area and can easily be performed from an apical approach.

Predictors of outcome in severe, asymptomatic aortic stenosis.

BACKGROUND: Whether to perform valve replacement in patients with asymptomatic but severe aortic stenosis is controversial. Therefore, we studied the natural history of this condition to identify predictors of outcome. METHODS: During 1994, we identified 128 consecutive patients with asymptomatic, severe aortic stenosis (59 women and 69 men; mean [+/-SD] age, 60+/-18 years; aortic-jet velocity, 5.0+/-0.6 m per second). The patients were prospectively followed until 1998. RESULTS: Follow-up information was available for 126 patients (98 percent) for a mean of 22+/-18 months. Event-free survival, with the end point defined as death (8 patients) or valve replacement necessitated by the development of symptoms (59 patients), was 67+/-5 percent at one year, 56+/-5 percent at two years, and 33+/-5 percent at four years. Five of the six deaths from cardiac disease were preceded by symptoms. According to multivariate analysis, only the extent of aortic-valve calcification was an independent predictor of outcome, whereas age, sex, and the presence or absence of coronary artery disease, hypertension, diabetes, and hypercholesterolemia were not. Event-free survival for patients with no or mild valvular calcification was 92+/-5 percent at one year, 84+/-8 percent at two years, and 75+/-9 percent at four years, as compared with 60+/-6 percent, 47+/-6 percent, and 20+/-5 percent, respectively, for those with moderate or severe calcification. The rate of progression of stenosis, as reflected by the aortic-jet velocity, was significantly higher in patients who had cardiac events (0.45+/-0.38 m per second per year) than those who did not have cardiac events (0.14+/-0.18 m per second per year, P<0.001), and the rate of progression of stenosis provided useful prognostic information. Of the patients with moderately or severely calcified aortic valves whose aortic-jet velocity increased by 0.3 m per second or more within one year, 79 percent underwent surgery or died within two years of the observed increase. CONCLUSIONS: In asymptomatic patients with aortic stenosis, it appears to be relatively safe to delay surgery until symptoms develop. However, outcomes vary widely. The presence of moderate or severe valvular calcification, together with a rapid increase in aortic-jet velocity, identifies patients with a very poor prognosis. These patients should be considered for early valve replacement rather than have surgery delayed until symptoms develop.

Congenital malformations of the right atrium and the coronary sinus: an analysis based on 103 cases reported in the literature and two additional cases.

STUDY OBJECTIVES: Congenital malformations of the right atrium (RA) and the coronary sinus (CS) are rare, and only sporadic cases have been reported. Little is known about the clinical relevance of this disorder. We report on two patients, one with a giant RA diverticulum, the other with a diverticulum of the CS, and review 103 cases of such malformations that have been reported previously. DESIGN: A MEDLINE search was performed to collect all cases of congenital malformations of the RA and the CS reported in the literature between 1955 and 1998. Cases were classified into the following categories: (1) congenital enlargement of the RA; (2) single diverticulum of the RA; (3) multiple diverticula of the RA; and (4) diverticulum of the CS. Clinical presentation and outcome of the different types of malformations were analyzed. RESULTS: The patients most frequently presenting with symptoms were those with diverticula of the CS (n = 28) followed by those with single diverticula of the RA (n = 13), multiple diverticula (n = 4), and congenital enlargements of the RA (n = 60). The percentages of symptomatic patients were 93, 84, 75, and 53%, respectively. Symptoms were frequently caused by arrhythmias. Supraventricular tachycardia (SVT) was found in 42 of the patients (40%) and was most common in patients with diverticula of the CS (24 of 28 patients) and multiple atrial diverticula (3 of 4 patients). Sudden cardiac death was reported more frequently in patients with diverticula of the CS (18%) compared to those with congenital enlargement of the RA (5%) or single or multiple diverticula of the RA (6%). All seven patients with diverticula of the CS who were not treated with catheter or surgical ablation eventually died. CONCLUSION: Congenital malformations of the RA and the CS frequently are associated with arrhythmias. SVT and sudden cardiac death have been reported in a significant percentage of patients with diverticula of the CS.