Aortic valve replacement in patients with aortic stenosis and severe left ventricular dysfunction

BACKGROUND: The outcome of aortic valve replacement for severe aortic stenosis is worse in patients with impaired left ventricular function. Such dysfunction in aortic stenosis may be reversible if caused by afterload mismatch, but not if it is caused by superimposed myocardial infarction. METHODS: From our echocardiography database, 55 patients with severe aortic stenosis (valve area < or =0.75 cm2) and ejection fractions of 30% or lower who subsequently underwent aortic valve replacement were included. The operative mortality and clinical follow-up were detailed. RESULTS: There were 10 perioperative deaths (operative mortality, 18%). Twenty (36%) of the 55 patients had a prior myocardial infarction. In the 35 patients without prior myocardial infarction, there was only 1 death (3%). In contrast, 9 of 20 patients with prior myocardial infarction died (mortality rate, 45%; P< or =.001). The factors significantly associated with perioperative death on univariate analysis (functional class, mean aortic gradient, and prior myocardial infarction) were entered into a model for stepwise logistic regression. This multivariate analysis showed that only prior myocardial infarction was independently associated with perioperative death (odds ratio, 14.9; 95% confidence interval, 2.4-92.1; P = .004). CONCLUSIONS: The risk of aortic valve replacement in patients with severe aortic stenosis and severely reduced left ventricular systolic function is extremely high if the patients have had a prior myocardial infarction. This information should be factored into the risk-benefit analysis that is done preoperatively for these patients, and it may preclude operation for some.     

Myocardial oxygen consumption in aortic valve disease with and without left ventricular dysfunction.

OBJECTIVE--To assess whether and to what extent myocardial oxygen consumption is modified by hypertrophy and alterations in contractility in patients with aortic valve disease and to evaluate the influence of regression of left ventricular hypertrophy and improvement of contractility on myocardial oxygen consumption after successful aortic valve replacement. DESIGN--A cohort analytical study to investigate the influence of the "explanatory" variables of myocardial oxygen consumption by multiple regression analysis. A comparison of myocardial oxygen consumption in preoperative patients with that after operation in a group with comparable severity of aortic valve disease before operation (analysis of covariance). PATIENTS--In six controls and in 43 patients with aortic valve disease and normal coronary arteries standard haemodynamic variables were measured, left ventricular biplane cineangiography performed, and coronary sinus blood flow measured by thermodilution. The patients were divided into three groups: 19 preoperative patients with normal ejection fraction (greater than or equal to 57%) (group 1); nine preoperative patients with reduced ejection fraction (less than 57%) (group 2); 16 postoperative patients (one with preoperative and postoperative measurements (group 3). Postoperative evaluation was performed 12-51 months after surgery. MAIN OUTCOME MEASUREMENTS--Myocardial oxygen consumption/100 g left ventricular muscle mass and its suspected "explanatory" variables--that is, peak systolic left ventricular circumferential wall stress, heart rate, contractility (assessed by left ventricular ejection fraction), and left ventricular muscle mass index. RESULTS--Multiple regression analysis showed that the product of peak systolic stress and heart rate (p less than 0.0001) and ejection fraction (p less than 0.03) were positively correlated with myocardial oxygen consumption/100 g and that left ventricular muscle mass index (p less than 0.002) was negatively correlated with myocardial oxygen consumption/100 g (r = 0.72; n = 50 measurements). Myocardial oxygen consumption per 100 g at a given stress-rate product was higher in the controls than in group 1 (hypertrophied ventricles with normal ejection fraction) and was also higher in group 1 than in group 2 (hypertrophied ventricles with reduced ejection fraction). In a subgroup of the postoperative patients with complete regression of hypertrophy and normalisation of contractility, myocardial oxygen consumption per 100 g at a given stress-rate product was indistinguishable from that in controls. CONCLUSIONS--When the actual stress-rate product was used as an index of overall left ventricular performance the results suggested that mechanical efficiency was increased in hypertrophied ventricles especially when contractility was decreased. These changes in mechanical efficiency seemed to be reversible during the postoperative course when muscle mass and contractility returned to normal.     

Myocardial oxygen consumption in aortic valve disease with and without left ventricular dysfunction.

OBJECTIVE--To assess whether and to what extent myocardial oxygen consumption is modified by hypertrophy and alterations in contractility in patients with aortic valve disease and to evaluate the influence of regression of left ventricular hypertrophy and improvement of contractility on myocardial oxygen consumption after successful aortic valve replacement. DESIGN--A cohort analytical study to investigate the influence of the "explanatory" variables of myocardial oxygen consumption by multiple regression analysis. A comparison of myocardial oxygen consumption in preoperative patients with that after operation in a group with comparable severity of aortic valve disease before operation (analysis of covariance). PATIENTS--In six controls and in 43 patients with aortic valve disease and normal coronary arteries standard haemodynamic variables were measured, left ventricular biplane cineangiography performed, and coronary sinus blood flow measured by thermodilution. The patients were divided into three groups: 19 preoperative patients with normal ejection fraction (greater than or equal to 57%) (group 1); nine preoperative patients with reduced ejection fraction (less than 57%) (group 2); 16 postoperative patients (one with preoperative and postoperative measurements (group 3). Postoperative evaluation was performed 12-51 months after surgery. MAIN OUTCOME MEASUREMENTS--Myocardial oxygen consumption/100 g left ventricular muscle mass and its suspected "explanatory" variables--that is, peak systolic left ventricular circumferential wall stress, heart rate, contractility (assessed by left ventricular ejection fraction), and left ventricular muscle mass index. RESULTS--Multiple regression analysis showed that the product of peak systolic stress and heart rate (p less than 0.0001) and ejection fraction (p less than 0.03) were positively correlated with myocardial oxygen consumption/100 g and that left ventricular muscle mass index (p less than 0.002) was negatively correlated with myocardial oxygen consumption/100 g (r = 0.72; n = 50 measurements). Myocardial oxygen consumption per 100 g at a given stress-rate product was higher in the controls than in group 1 (hypertrophied ventricles with normal ejection fraction) and was also higher in group 1 than in group 2 (hypertrophied ventricles with reduced ejection fraction). In a subgroup of the postoperative patients with complete regression of hypertrophy and normalisation of contractility, myocardial oxygen consumption per 100 g at a given stress-rate product was indistinguishable from that in controls. CONCLUSIONS--When the actual stress-rate product was used as an index of overall left ventricular performance the results suggested that mechanical efficiency was increased in hypertrophied ventricles especially when contractility was decreased. These changes in mechanical efficiency seemed to be reversible during the postoperative course when muscle mass and contractility returned to normal.     

单纯性主动脉瓣人工瓣膜置换术对主动脉瓣病变患者术后左心功能的影响

目的 观察单纯性主动脉瓣人工瓣膜置换术对主动脉瓣病变患者术后左心功能的影响.方法 选择我院收治的主动脉瓣病变患者96例,均行单纯性主动脉瓣人工瓣膜置换术,二维超声心动图测量左室舒张末内径(LVDd)、左室收缩末内径(LVDs)、左室射血分数(LVEF),计算左室短轴缩短率(FS)、左室心肌重量指数(LVMI).结果 与术前比较,术后1周LVDd、LVDs降低,术后6个月LVDd、LVDs、LVMI降低,LVEF、FS升高(P均＜0.05);与术后1周比较,术后6个月LVDd、LVDs、LVMI降低,LVEF、FS升高(P均＜0.05).结论 主动脉瓣病变患者通过积极有效的手术干预,术后左心功能状态可以得到明显改善.     

超声心动图研究单纯主动脉瓣置换术后左心室的可复性

目的:观察单纯主动脉瓣置换术后左心室形态和功能的可恢复性。方法:回顾分析施行单纯主动脉瓣置换术后49例非心房颤动患者的超声心动图资料。结果:患者术前左室舒张末内径(LVEDD)较对照组明显扩大,LVEDD在术后早期(术后3周~6个月)及术后中期(术后1~2年)均有明显减小。收缩期室间隔厚度及收缩期左室后壁厚度在手术前后差异无统计学意义(P>0.05)。术后早期及中期患者的左室射血分数及短轴缩短分数较术前均明显提高,达正常水平。结论:主动脉瓣置换术促进术前扩大受损的左心室恢复,术后左室射血分数及LVEDD明显改善。     

Minimally invasive aortic valve replacement in left ventricular dysfunction

The safety and benefit of minimally invasive aortic valve replacement in patients with left ventricular dysfunction has not been well investigated. We conducted a retrospective review of 140 patients with ejection fraction 相似文献   

Assessment of left ventricular and aortic valve function after aortic balloon valvuloplasty in adult patients with critical aortic stenosis

Preliminary reports have documented the utility of balloon aortic valvuloplasty as a palliative treatment for high-risk patients with critical aortic stenosis, but the effect of this procedure on cardiac performance has not been studied in detail. Accordingly, 32 patients (mean age 79 years) with long-standing, calcific aortic stenosis were treated at the time of cardiac catheterization with balloon dilatation of the aortic valve, and serial changes in left ventricular and valvular function were followed before and after valvuloplasty by radionuclide ventriculography, determination of systolic time intervals, and Doppler echocardiography. Prevalvuloplasty examination revealed heavily calcified aortic valves in all patients, a mean peak-to-peak aortic valve gradient of 77 +/- 27 mm Hg, a mean Fick cardiac output of 4.6 +/- 1.4 liters/min, and a mean calculated aortic valve area of 0.6 +/- 0.2 cm2. Subsequent balloon dilatation with 12 to 23 mm valvuloplasty balloons resulted in a fall in aortic valve gradient to 39 +/- 15 mm Hg, an increase in cardiac output to 5.2 +/- 1.8 liters/min, and an increase in calculated aortic valve area to 0.9 +/- 0.3 cm2. Individual hemodynamic responses varied considerably, with some patients showing major increases in valve area, while others demonstrated only small increases. In no case was balloon dilatation accompanied by evidence of embolic phenomena. Supravalvular aortography obtained in 13 patients demonstrated no or a mild (less than or equal to 1+) increase in aortic insufficiency. Serial radionuclide ventriculography in patients with a depressed left ventricular ejection fraction (i.e., that less than or equal to 55%) revealed a small increase in ejection fraction from 40 +/- 13% to 46 +/- 12% (p less than .03). In addition, for the study group as a whole there was a decrease in left ventricular end-diastolic volume index (113 +/- 38 to 101 +/- 37 ml/m2, p less than .003), a fall in stroke-volume ratio (1.49 +/- 0.44 to 1.35 +/- 0.33, p less than .04), and no immediate change in left ventricular peak filling rate (2.05 +/- 0.77 to 2.21 +/- 0.65 end-diastolic counts/sec, p = NS). Serial M mode echocardiography and phonocardiography showed an increase in aortic valve excursion (0.5 +/- 0.2 to 0.8 +/- 0.2 cm, p less than .001), a decrease in time to one-half carotid upstroke (80 +/- 30 to 60 +/- 10 msec, p less than .001), and a small decrease in left ventricular ejection time (0.44 +/- 0.03 to 0.42 +/- 0.02 sec, p less than .001).(ABSTRACT TRUNCATED AT 400 WORDS)     

Pre- and postoperative left ventricular contractile function in patients with aortic valve disease.

In 43 patients left ventricular micromanometry and cineangiography were performed preoperatively and and 20 months after aortic valve replacement. A score of left ventricular functional impairment, derived from 5 to 8 haemodynamic variables, was calculated as: number of pathological indices x 100/total number of determined indices. Preoperatively the score of left ventricular functional impairment amounted to 35 per cent in group 1 (aortic stenosis: n = 19), to 61 per cent in group 2 (combined lesion:n = 15) (P less than 0.05), and to 87 per cent in group 3 (aortic regurgitation: n = 9) (P less than 0.001). In contrast, the functional classification according to the NYHA showed similar impairment in the 3 groups. Postoperatively the score of left ventricular functional impairment decreased significantly in all 3 groups to 10, 16, and 27 per cent, respectively, but the score of group 3 remained raised (P less than 0.05) as compared with that of group 1. The patients with residual left ventricular dysfunction had a higher preoperative left ventricular muscle mass than the patients with normal or near normal postoperative left ventricular function. It is concluded that (1) at similar functional impairment according to the NYHA classification left ventricular contractile function is more severely impaired in aortic regurgitation and in aortic regurgitation + aortic stenosis than in aortic stenosis alone, (2) left ventricular function improves significantly after valve replacement in all three forms of aortic valve disease, (3) residual functional impairment is greater in aortic regurgitation than in aortic stenosis or aortic stenosis + aortic regurgitation, and (4) persistent postoperative left ventricular functional impairment is found in the patients with severe preoperative hypertrophy.     

Effects of valve replacement on left ventricular function in patients with aortic regurgitation and severe ventricular disease

BACKGROUND AND AIM OF THE STUDY: Longstanding aortic regurgitation (AR) can result in left ventricular (LV) dysfunction that may reverse after aortic valve replacement (AVR). Stentless valves may result in a more rapid recovery in function due to a more physiological flow and lower outflow resistance. METHODS: The effect of AVR on LV function was studied in 47 patients who received either a stentless (n = 33) or stented (n = 14) valve for isolated AR. All patients had evidence of pre-existing LV dysfunction (end-systolic dimension (ESD) >50 mm). Patients were studied using transthoracic echocardiography at baseline, postoperatively, and at 2.5-year follow up. RESULTS: Preoperatively, there were no differences in LV dimensions. The end-diastolic dimension fell from 75 +/- 10 mm to 61 +/- 10 mm postoperatively and to 52 +/- 10 mm at follow up in the stentless group (p <0.001), and ESD fell from 54 +/- 10 mm to 36 +/- 8 mm at follow up (p <0.001). There were no significant early changes in patients who received stented valves, though LV dimensions fell at follow up. Fractional shortening (FS) increased from 25 +/- 8% in the postoperative period to 31 +/- 7% in the stentless group (p <0.001), but there was no change in the stented group (20 +/- 7% versus 23 +/- 8%). In the stentless group, LV mass fell from 366 +/- 104 g to 276 +/- 68 g postoperatively and to 219 +/- 79 g at follow up (p <0.001); there was no postoperative change in the stented group, though a late reduction occurred, from 349 +/- 51 g preoperatively to 265 +/- 61 g at follow up (p = 0.06). CONCLUSION: For patients with AR and LV dysfunction, AVR with a stentless prosthesis offers early reductions in LV dimensions, improved LV function, and regression of LV mass. In patients who received a stented valve, these improvements were delayed and less complete. Hence, for some patients with AR and LV dysfunction, a stentless prosthesis may be preferable.     

Risk stratification and management of aortic stenosis with concomitant left ventricular dysfunction

Opinion statement Aortic stenosis is a common clinical problem. The development of symptoms usually precedes the development of left ventricular (LV) dysfunction. Therefore, patients with concomitant severe aortic stenosis and LV dysfunction comprise a minority with this condition, albeit a clinically challenging group to manage. Because the only proven therapy for aortic stenosis is surgical valve replacement, the approach to the management of a patient with aortic stenosis and LV dysfunction primarily centers on risk stratification and the decision of whether to operate. Patients with aortic stenosis and low transvalvular gradients constitute a distinctly high-risk group, particularly when evidence of contractile reserve is absent after challenge with dobutamine. In the absence of any effective medical therapies, it is increasingly clear that even high-risk patients lacking contractile reserve may benefit from surgical valve replacement. However, evolving experimental percutaneous solutions may offer new management options for high-risk patients in the future.     

Retrograde left ventricular catheterization in patients with an aortic valve prosthesis

Twenty-seven consecutive patients with an aortic valve prosthesis were evaluated with retrograde left ventricular catheterization. The prosthesis was successfully crossed, permitting hemodynamic and angiographic evaluation of function of the prosthetic valve, left ventricle and mitral valve in all 27 cases. No complications were encountered. In patients with active endocarditis or recent embolization, the retrograde technique was avoided when possible, and attempts were made to utilize other techniques for study. However, three such patients were evaluated with the retrograde technique without complication. Examination of pressure tracings and cineangiographic films suggested only minor interference with valve poppet movement induced by the catheter transversing the valve. In three cases, hemodynamic data were recorded with the catheter crossing the prosthesis at one time and a paraprosthetic valve defect at another time. Identical gradients were recorded. This series documents the safety and efficacy of the retrograde approach, which is proposed as an alternative to the transseptal technique and left ventricular puncture.     

Long-term survival and functional results after aortic valve replacement in asymptomatic patients with chronic severe aortic regurgitation and left ventricular dysfunction

OBJECTIVES: We examined the influence of medical treatment on the results of surgery in terms of long-term survival and functional results in patients with chronic, severe aortic regurgitation (AR). BACKGROUND: Asymptomatic patients with AR and a reduced left ventricular ejection fraction (LVEF) are at high risk because of a higher-than-expected long-term mortality. The influence of preoperative medical therapy on the outcome after aortic valve replacement (AVR) is not well known. METHODS: Surgery was indicated for the appearance of a reduced LVEF (<50%). At the time of AVR, there were 134 patients treated with nifedipine (group A), and 132 received no medication (group B). RESULTS: Operative mortality was similar in the two groups (0.75% vs. 0.76%, p = NS). The LVEF normalized in all of group A, whereas it remained abnormal in 36 group B patients (28%). At 10-year follow-up, LVEF persisted higher in group A (62 +/- 5% vs. 48 +/- 4%, p < 0.001). Five-year survival was similar in the two groups (94 +/- 2% vs. 94 +/- 3%, p = NS). Group A showed a 10-year survival not different from expected and significantly higher than that in group B (85 +/- 4% vs. 78 +/- 5%, p < 0.001), which had a worse survival than expected. CONCLUSIONS: Unloading treatment with nifedipine in AR allows one to indicate AVR at the appearance of a reduced LVEF with a low operative mortality and an optimal long-term outcome. The concept of surgical correction of AR indicated for reduced LVEF may not be applied to all patients. Indeed, in a large amount of untreated patients, a reduced LVEF preoperatively is not reversed by prompt surgery, indicating irreversible myocardial damage, and 10-year survival is worse than expected.     

Left ventricular diastolic dysfunction late after aortic valve replacement in patients with aortic stenosis

Patients with severe aortic stenosis (AS) are known to have increased left ventricular (LV) mass and diastolic dysfunction. It has been suggested that LV mass and diastolic function normalize after aortic valve replacement (AVR). In the present study, change in LV mass index and diastolic function 10 years after AVR for AS was evaluated. Patients who underwent AVR from 1991 to 1993 (n = 57; mean age 67 +/- 8.6 years at AVR, 58% men) were investigated with Doppler echocardiography preoperatively and 2 and 10 years postoperatively. Diastolic function was evaluated by integrating mitral and pulmonary venous flow data. Expected values for each patient, taking age into consideration, were defined using a control group (n = 71; age range 18 to 83 years). Patients were classified into 4 types: normal diastolic function (type A), mild diastolic dysfunction (type B), moderate diastolic dysfunction (type C), and severe diastolic dysfunction (type D). There was a reduction in LV mass index between the preoperative (161 +/- 39 g/m2) and 2-year follow-up (114 +/- 28 g/m2) examinations (p <0.0001), but no further reduction was seen at 10 years (119 +/- 49 g/m2). The percentage of patients with increased LV mass index decreased from 83% preoperatively to 29% at 2-year follow-up (p <0.001). The percentage of patients with moderate to severe LV diastolic dysfunction (types C and D) was unchanged between the preoperative (7%) and 2-year follow-up (13%) examinations (p = 0.27). The percentage of patients increased at 10-year follow-up to 61% (p <0.0001). In conclusion, this reveals the development of moderate to severe diastolic dysfunction 10 years after AVR, despite a reduction in the LV mass index.