After Aortic Valve Replacement For Aortic Stenosis Research Articles

Incidence and Risk Factors for Long-Term Persistence of Diastolic Dysfunction after Aortic Valve Replacement for Aortic Stenosis Compared with Aortic Regurgitation

(1) Background: Severe left ventricular (LV) diastolic dysfunction with a restrictive diastolic pattern (LVDFP) is generally associated with a worse prognosis. Its evolution and reversibility in the short- and medium-term after aortic valve replacement (AVR) has been little-studied. We aimed to evaluate the evolution of LV remodeling and LV systolic and diastolic function after AVR in aortic stenosis (AS) patients compared to aortic regurgitation (AR). Moreover, we tried to identify the main predictive parameters for postoperative evolution (cardiovascular hospitalization or death and quality of life) and the independent predictors for the persistence of restrictive LVDFP after AVR. (2) Methods: A five-year prospective study on 397 patients undergoing AVR for AS (226 pts) or AR (171 pts), evaluated clinically and by echocardiography preoperatively and until 5 years postoperatively. (3) Results: 1. In patients with AS, early post AVR, LV dimensions decreased and diastolic filling and LV ejection fraction (LVEF) improved more rapidly compared to patients with AR. At 1 year postoperatively, persistent restrictive LVDFP was found especially in the AR group compared to the AS group (36.84% vs. 14.16%). 2. Cardiovascular event-free survival at the 5-year follow-up was lower in the AR group (64.91% vs. 87.17% in the AS group). The main independent predictors of short- and medium-term prognosis after AVR were: restrictive LVDFP, severe LV systolic dysfunction, severe pulmonary hypertension (PHT), advanced age, severe AR, and comorbidities. 3. The persistence of restrictive LVDFP after AVR was independently predicted by: preoperative AR, the E/Ea ratio > 12, the LA dimension index > 30 mm/m2, an LV endsystolic diameter (LVESD) > 55 mm, severe PHT, and associated second-degree MR (p < 0.05). (4) Conclusions: AS patients had an immediate postoperative evolution in terms of LV remodeling, and LV systolic and diastolic function were more favorable compared to those with AR. The restrictive LVDFP was reversible, especially after the AVR for AS. The main prognostic predictors were the presence of restrictive LVDFP, advanced age, preoperative AR, severe LV systolic dysfunction, and severe PHT.

Impact of Aortic Valve Replacement for Aortic Stenosis on Coexisting Mitral Stenosis.

Purpose: The course of coexisting mitral valve stenosis is not clear after aortic valve replacement (AVR) for aortic stenosis (AS). We investigated the effect of AVR for AS on coexisting mitral stenosis (MS).Methods: Between January 2002 and December 2019, 1338 consecutive patients underwent surgical AVR at Shiga University of Medical Science. Of them, 34 patients with moderate MS (mitral valve area [MVA]: 1.5–2.0 cm2) were included in the present study. We evaluated the postoperative clinical outcomes in these patients.Results: Mean MVA in our cohort significantly increased 1 week after operation compared with preoperative values, and the change was maintained for 5 years after surgery. Follow-up was completed in 94.1% (32/34) patients, and mean follow-up duration was 4.0 ± 3.0 years. No patients underwent mitral surgery for remaining MS after AVR during postoperative follow-up.Conclusion: AVR for AS resulted in increased MVA in patients with MS, and the change was maintained during follow-up.

The Association between Aortic Valve Weight, Echocardiographic Indices, and All-Cause Death in 1,046 Patients Undergoing Surgical Aortic Valve Replacement for Aortic Stenosis

Background: Aortic valve weight (AVW), a flow independent measure of aortic stenosis (AS) severity, is reported to have heterogeneous associations with the echocardiographic variables used for AS evaluation. Controversy exists regarding its impact on survival after aortic valve replacement (AVR). Objective: We sought to determine the association between AVW with echocardiographic measures of AS severity and all-cause mortality after surgical AVR. Methods: One thousand and forty-sixconsecutive patients underwent surgical AVR for AS, the excised valves were weighed, and an echocardiogram was done before surgery. Results: Males had heavier valves than females, for both absolute and body surface are (BSA)-indexed values (2.78 ± 1.23 vs. 2.08 ± 0.68 g, p < 0.001; and 1.38 ± 0.61 vs. 1.19 ± 0.41 g/m², p < 0.001, respectively). In a restricted cohort of 634 patients with isolated severe AS and normal ejection fraction, the correlations of AVW with echocardiographic variables of AS were modest, the strongest being with the dimensionless index (r = –0.27 and –0.26 for male and female, both p < 0.01). Stratified by stroke volume index and mean gradient (MG), no associations were found in the low-gradient groups (i.e., MG <40 mmHg). At a median follow-up of 3.5 years, there were only 244 deaths in the entire cohort. Mortality was not related to AVW, except in females who displayed an inverse relationship (HR = 0.67; 95% CI 0.47–0.95) only when it was analyzed as a continuous variable. Conclusions: The weak correlation between AVW with the echocardiographic indices of AS may reflect its complex pathophysiology, heterogeneous hemodynamics, and possible pitfalls in the current echocardiographic methods used in clinical practice. The prognostic value of AVW after AVR warrants further evaluation.

Levosimendan or milrinone for right ventricular inotropic treatment?-A secondary analysis of a randomized trial.

The aim of the present study was to compare the effects of milrinone and levosimendan on right ventricular (RV) inotropy and lusitropy in patients after aortic valve replacement (AVR) for aortic stenosis, a procedure in which an abnormal postoperative RV function may be seen. In a prospective, blinded trial, 31 patients were randomized to receive either milrinone (0.4 and 0.8µg/kg/min, n=16) or levosimendan (0.1 and 0.2µg/kg/min, n=15) after AVR for aortic stenosis. RV performance, afterload (pulmonary arterial elastance), RV strain, systolic (SR-S) and early diastolic (SR-E) strain rate were measured by pulmonary artery thermodilution catheterization and transoesophageal two-dimensional speckle tracking echocardiography. To circumvent the indirect effects of inodilator-induced hemodynamic changes on RV systolic and diastolic deformation, pulmonary arterial elastance, central venous pressure and heart rate were maintained constant by atrial pacing, plasma volume expansion with colloids and phenylephrine-induced vasoconstriction during treatment with the inotropes. A dose-dependent increase in stroke volume index and cardiac index by approximately 20% were seen with both agents at the highest doses, with no difference between groups (P=.792 and 0.744, respectively). In both groups, RV strain and SR-S dose-dependently increased by 20% and 15%-19%, respectively, at the highest doses (P=.742 and 0.259, respectively) with no difference between groups. SR-E improved by both agents 20%-24% at the highest dose with no difference between groups (P=.714). The direct RV inotropic and lusitropic effects of levosimendan and milrinone were comparable at clinically relevant infusion rates.

NT-proBNP and postoperative heart failure in surgery for aortic stenosis

ObjectivePostoperative heart failure (PHF) after aortic valve replacement (AVR) for aortic stenosis (AS) may initially appear mild and transient but has serious long-term consequences. Methods to assess PHF are not...

Outcomes after aortic valve replacement for aortic valve stenosis, with or without concomitant coronary artery bypass grafting.

To assess the effects of concomitant coronary artery bypass grafting (CABG), we analyzed the outcomes after aortic valve replacement (AVR) for aortic stenosis (AS) with and without coronary artery bypass grafting (CABG) at our institution. Between 2002 and 2014, 605 consecutive patients underwent AVR for AS. Of these, the 275 who received isolated AVR (Group A) and the 122 who received both AVR and CABG (Group AC) patients were enrolled, after the exclusion of 8 patients who underwent reoperation and 200 who received other concomitant surgery. AVR and all bypass anastomoses were performed under intermittent retrograde cold blood cardioplegia. Multivariate analysis was used to assess any association of concomitant CABG with morbidity and mortality. Kaplan-Meier analysis was used to assess all-cause mortality. No significant difference in 30-day mortality was found between Group A and Group AC (1.5% vs. 0.8%, P = 1.000). Nor did post-discharge survival differ significantly between the two groups (P = 0.20). Likewise, multivariate analysis showed that concomitant CABG was not associated with significantly greater in-hospital or mid-term mortality. Operative morbidities were comparable between the two groups, in terms of stroke (1.8% vs. 3.3%, P = 0.466), prolonged ventilation (4.0% vs. 5.5%, P = 0.565), deep sternal infection (1.8% vs. 3.3%, P = 0.466), and acute renal failure (0.4% vs. 1.6% P = 0.176). Concomitant CABG at the time of AVR was performed without increasing early- or mid-term mortality. This absence of increased risk deserves consideration when choosing between different treatment strategies.

Usefulness of Electrocardiographic Strain to Predict Survival After Surgical Aortic Valve Replacement for Aortic Stenosis

Electrocardiographic (ECG) strain has been reported as a specific marker of midwall left ventricular (LV) myocardial fibrosis, predictive of adverse clinical outcomes in aortic stenosis (AS), but its prognostic impact after aortic valve replacement (AVR) is unknown. We aimed to assess the impact of ECG strain on long-term mortality after surgical AVR for AS. From January 2005 to January 2014, patients with interpretable preoperative ECG who underwent isolated AVR for AS were included. ECG strain was defined as ≥1-mm concave downslopping ST-segment depression with asymmetrical T-wave inversion in lateral leads. Mortality was assessed over a follow-up period of 4.8 ± 2.7 years. Among the 390 patients included, 110 had ECG strain (28%). They had significantly lower body mass index, higher mean transaortic pressure gradient and Cornell-product ECG LV hypertrophy than in those without ECG strain. There was also a trend for lower LV ejection fraction in patients with ECG strain as compared with those without. Patients with ECG strain had significantly lower 8-year survival than those without. ECG strain remained associated with reduced survival both in patients with and without LV hypertrophy (p <0.0001 for both). After adjustment, ECG strain remained a strong and independent determinant of long-term survival (hazard ratio 4.4, p <0.0001). Similar results were found in patients with LV hypertrophy or without LV hypertrophy. In the multivariate model, the addition of ECG strain provided incremental prognostic value (p <0.0001). In conclusion, in patients with AS, ECG strain is associated with 4-fold increased risk of long-term mortality after isolated AVR, regardless of preoperative LV hypertrophy.

Effect of aortic pericardial valve choice on outcomes and left ventricular mass regression in patients with left ventricular hypertrophy

ObjectivesWe sought to assess the effect of 2 contemporary pericardial valves on left ventricular mass regression and clinical outcomes after aortic valve replacement (AVR) in patients with aortic stenosis (AS). MethodsPatients were followed postoperatively in a dedicated valve clinic. A propensity score was derived for each patient and used to adjust all analyses. Longitudinal analysis was performed using a repeated measures growth curve model. Survival analysis was assessed with a Cox proportional hazards model. ResultsSince February 2011, 258 patients with AS and left ventricular hypertrophy underwent AVR with the Trifecta (TR) (St Jude Medical, St Paul, Minn) or Perimount Magna Ease (ME) (Edwards LifeSciences, Irvine, Calif) bioprosthesis. There were longer bypass and crossclamp times and the indexed left ventricular outflow tract was smaller in the TR group. For the TR and ME, respectively, peak (14.4 ± 5.1 mm Hg vs 20.9 ± 7.2 mm Hg; P < .001) and mean (7.3 ± 2.7 mm Hg vs 10.9 ± 4.3 mm Hg; P < .001) gradients were significantly smaller postoperatively in the TR group. There was greater total mass regression (44.3 g/m2; 95% confidence interval [CI], 36.3-52.3 vs 29.5; 95% CI, 20.4-38.5 g/m2; P = .020) and mass regression over time in the TR group compared with the ME group (P = .016). Freedom from readmission, congestive heart failure, and the composite outcome of all-cause mortality, readmission, and congestive heart failure at 2.5 years was significantly improved in the TR group (composite outcome in TR and ME groups, respectively, 90.2; 95% CI, 81.9-94.9 and 78.2; 95% CI, 67.1-86.0; P = .013) ConclusionsTR use was associated with significantly increased left ventricular mass regression and improved intermediate-term clinical outcome in patients with left ventricular hypertrophy undergoing AVR for AS, compared with use of the ME.

Impact of secondary hyperparathyroidism on ventricular mass regression after aortic valve replacement for aortic stenosis in hemodialysis-dependent patients.

In hemodialysis (HD)-dependent patients, secondary hyperparathyroidism induces cardiac hypertrophy. This study investigated whether parathyroid hormone (PTH) levels affect the degree of left ventricular (LV) mass regression in HD patients after aortic valve replacement (AVR) for aortic stenosis (AS). We retrospectively obtained preoperative and 2-year postoperative echocardiography and intact PTH measurements in 88 HD patients who underwent AVR, with bioprostheses (n = 35, 40%) and mechanical valves (n = 53, 60%) of effective orifice area >0.80 cm2/m2, between January 1997 and December 2010. The LV mass decreased significantly from 308 ± 88 to 217 ± 68 g at follow-up of 28 ± 4 months after AVR (p < 0.001). The LV mass regression at follow-up was inversely related to preoperative PTH values (R = 0.44, p = 0.001). The LV mass regression at follow-up was significantly smaller in the patients (n = 47) with PTH ≥100 pg/mL than in those (n = 41) with PTH <100 pg/mL throughout the study period (61 ± 75 versus 108 ± 49 g, p < 0.0001). After adjusting for female sex, hypertension, and baseline LV mass, high PTH values were found to be independent predictor of less LV mass regression at 2-year follow-up (β = 0.23, r2 = 0.24, p = 0.02). In conclusion, the HD patients with high levels of PTH presented with less LV mass regression after AVR for AS without patient-prosthesis mismatch. Secondary hyperparathyroidism may impair regression of cardiac hypertrophy after AVR in HD patients with AS.

Delayed-Onset Systolic Anterior Motion of the Mitral Valve After Aortic Valve Replacement for Severe Aortic Stenosis

Systolic anterior motion (SAM) of the mitral valve after aortic valve replacement (AVR) for severe aortic stenosis (AS) is one of the causes of perioperative left ventricular outflow tract (LVOT) obstruction in older patients. A 90-year-old woman underwent AVR with a 19-mm bioprosthesis for symptomatic aortic valve stenosis. Preoperative transthoracic echocardiography (TTE) showed left ventricular hypertrophy, with LVOT obstruction and mild mitral regurgitation (MR). Intraoperative transesophageal echocardiography and postoperative TTE showed that the degree of MR was unchanged after surgery. The patient's postoperative course was uneventful. However, she developed shortness of breath 6 months after discharge. A subsequent TTE showed significant LVOT obstruction and SAM, which resulted in moderate to severe MR. Because of the patient's advanced age, cibenzoline was administered to decrease the left ventricular pressure gradient (LVPG) and improve the left ventricular diastolic function. Two months after administration of cibenzoline, a TTE showed decreased LVPG, trivial MR, and the absence of SAM. This case clearly demonstrated that cibenzoline improved the SAM of the mitral valve that arose after AVR for AS in a remote postoperative period.

Residual compromised myocardial contractile reserve after valve replacement for aortic stenosis

Despite recovery of left ventricular (LV) function and morphology after aortic valve replacement (AVR) for aortic stenosis (AS), its relationship with exercise capacity remains unknown. Twenty-one AVR patients (age 61 ± 12 years, 14 male) with normal ejection fraction (EF, 64 ± 7%) and 21 age- and sex-matched controls (57 ± 9 years, 10 male, EF 68 ± 8%) were studied. All subjects performed semi-supine bicycle exercise and speckle tracking echocardiography (STE) study. Peak oxygen consumption (pVO(2)) was collected during semi-supine bicycle exercise. Systolic (GLSRs) and early diastolic (GLSRe) longitudinal strain rate using STE and Doppler echocardiographic parameters were measured at rest, submaximal, peak exercise, and 4 min after exercise. The two groups had comparable resting echocardiographic measurements. At peak exercise, pVO(2) was lower in patients than controls (18.5 ± 4.5 vs. 22.1 ± 4.3 L/min/kg, P < 0.05). GLSRs (0.98 ± 0.28 vs. 1.55 ± 0.30 1/s, P < 0.001), septal Sm (7.9 ± 1.4 vs. 11.1 ± 2.3 cm/s, P < 0.001) and their changes between rest and peak exercise (ΔGLSRs: 0.16 ± 0.33 vs. 0.68 ± 0.27 1/s, P < 0.001; ΔSm 2.29 ± 2.23 vs. 4.63 ± 2.29 cm/s, P < 0.01) were significantly lower in patients than controls. There was no correlation between pVO(2) and any echocardiographic measurements in controls. In patients, pVO(2) correlated with peak exercise GLSRs (r = 0.60, P = 0.0007), septal Sm (r = 0.65, P = 0.002), and Em (r = 0.57, P = 0.009). In a multivariate model, peak exercise GLSRs (β = 7.18, P = 0.03) was the only independent predictor of pVO(2) in the patients group. Exercise capacity is subnormal after AVR for AS, irrespective of normal LVEF suggesting residual compromised myocardial functional reserve.

Improvement of Ultrasonic Myocardial Properties after Aortic Valve Replacement for Pure Severe Aortic Stenosis: The Predictive Value of Ultrasonic Tissue Characterization for Left Ventricle Reverse Remodeling

Aortic stenosis leads to left ventricular hypertrophy and accumulation of fibrillar collagens. The analysis of integrated backscatter (IBS) parameters provides information on ultrasonic myocardial properties. The study population consisted of 58 patients with aortic stenosis. They were followed up for an average 18 ± 5 months after aortic valve replacement (AVR). Traditional transthoracic echocardiography and analysis of IBS reflectivity were performed before AVR and during the control visit after AVR. A significant reduction in left ventricular mass index, a significant increase in the mean cyclic variation of IBS, and a decrease in absolute end-diastolic IBS intensity were observed after AVR. These data suggest improvements in ultrasonic myocardial properties after AVR. Preoperative analysis of IBS parameters might provide additional information for predicting left ventricular reverse remodeling in patients a mean of 1.5 years after AVR for aortic stenosis.

Is Concomitant Surgery for Moderate Functional Mitral Regurgitation Indicated during Aortic Valve Replacement for Aortic Stenosis? A Systematic Review and Evidence-Based Recommendations

Mitral regurgitation (MR) is associated with poor clinical outcomes. Functional MR is often associated with aortic stenosis (AS) and may resolve after aortic valve replacement (AVR). The objective of this study was to derive evidence-based recommendations regarding surgical intervention for moderate functional MR at the time of AVR for AS. An exhaustive literature search strategy including Medline, Embase, the Cochrane library, and meeting abstracts was performed. Studies meeting inclusion criteria were critically appraised and data pooled according to accepted meta-analysis techniques. The primary outcome was change in moderate MR after isolated AVR. Secondary outcomes were the impact of functional MR on survival and identifying factors that predict progression of MR, in patients undergoing isolated AVR for AS. Thirteen nonrandomized studies including 2113 patients were reviewed. A total of 268 patients had preoperative moderate functional MR and AS. All studies were appraised as poor methodological quality. After isolated AVR a trend toward improvement in MR was observed. Left ventricular dysfunction, left atrial enlargement, and atrial fibrillation were associated with progression of MR after AVR. However, the impact of residual MR on late survival was not consistent. Pooling current evidence provided inconclusive evidence to make clinical practice recommendations for or against routine surgical intervention of moderate MR at the time of AVR for AS. The incidence of this pathology makes further clinical trial studies warranted.

Aortic root motion remodeling after aortic valve replacement - implications for late aortic dissection

Aortic root motion was previously identified as an additional risk factor for aortic dissection. This study analyzed if the magnitude of aortic root motion changed in patients after aortic valve replacement (AVR) and acute proximal aortic dissection. An institutional database (1984-2005) was used to measure the downward motion of the aortic root (perpendicular to the plane of the sinotubular junction) in contrast injections in 48 patients with aortic insufficiency (AI), aortic stenosis (AS) and proximal aortic dissection pre- and postoperatively, when available. Postoperative aortic root motion was significantly reduced after AVR for AI, while it was significantly increased after AVR for AS. By contrast, aortic root motion was unchanged when functional AI due to paravalvular leak was present post-AVR for AI. In patients with acute aortic dissection, both aortic root motion and aortic diameter were unchanged from pre-dissection. However, in patients who dissected again, aortic root motion was significantly smaller than pre-dissection, and the aortic diameter was significantly less than at first dissection. Removal of aortic stenosis was associated with increased aortic root motion, theoretically heightening the threat of dissection posed to the aortic wall by mechanical stress, although this was not confirmed by our study of dissection patients. Yet, mechanical principles command to include higher magnitude of aortic root motion during follow-up of patients after AVR as an additional risk factor for dissection.

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.

Hemodynamic function of the standard St. Jude bileaflet disc valve has no clinical impact 10 years after aortic valve replacement

Objectives: Size mismatch and impaired left ventricular function have been shown to determine the hemodynamic function of the standard St. Jude bileaflet disc valve early after aortic valve replacement (AVR). We aimed to analyse St. Jude valve hemodynamic function and its clinical impact in the survivors of a prospective series 10 years after AVR for aortic stenosis. Design: Forty-three survivors aged 32–90 years from a prospective series attended a follow-up study with Doppler echo and radionuclide cardiography 10 years after AVR for aortic stenosis. Six patients with significant left sided valve regurgitation were excluded from further analysis: they had significantly lower St. Jude valve gradient and left ventricular ejection fraction (LVEF) and larger mass index (LVMi) than 37 without. Results: In the 37 patients without left sided valve regurgitation peak and mean gradients were inversely related to St. Jude valve geometric orifice area (GOA) indexed for either body surface area or left ventricular end-diastolic dimension (LVEDD). The gradients correlated directly with LVEDD but not with LVEF or LVMi. Eleven patients with hypertension had higher peak gradients (31±13 versus 22±8 mmHg, p < 0.05), lower LVEF, and higher LVEDD and LVMi than 26 without. Peak gradient was greater than 35 mmHg in five hypertensive patients with normal LVEF but lesser than 30 mmHg in six with impaired LVEF. Supranormal LVEF and severe size mismatch identified the remaining patients (N = 3) with peak gradient above 35 mmHg. In a multilinear regression analysis GOA indexed for LVEDD, hypertension, and LVEF were independently related to peak gradient. Conclusion: High gradients of the standard St. Jude bileaflet disc valve 10 years after AVR was primarily related to systemic hypertension and mismatch between valve and left ventricular cavity size. Hypertension and left sided valve regurgitation, but not St. Jude valve gradient or size mismatch, were the dominant determinants of left ventricular hypertrophy and impaired function.

Does the type of prosthesis influence early left ventricular mass regression after aortic valve replacement? Assessment with magneticresonance imaging

Background Debate exists regarding selection of the prosthesis type most likely to maximize early left ventricular (LV) mass regression after aortic valve replacement (AVR) for stenotic valvular disease. The aim of this study was to compare the degree of LV mass regression measured by MRI 6 months after prospectively randomized valve implantation for two biological prostheses, stented and stentless, and for two mechanical valves, tilting disc and bileaflet. Methods Thirty-nine consecutive patients with predominant aortic stenosis accepted for elective AVR were studied. Twenty patients requiring a tissue prosthesis were randomly assigned to receive either a Freestyle or Mosaic valve. The remaining 19 patients in whom mechanical prosthesis was indicated were randomly assigned to receive either an Ultracor or an ATS valve. Results There was no difference in valve size implanted between the compared groups. LV mass measurements were performed with MRI (1.5-T Vision, Siemens, Germany) immediately before and 6 months after surgery. All valve types produced significant postoperative reduction in LV mass compared with preoperative values ( P < .01). Percent change in LV mass regression was similar between the two porcine valve types, Mosaic (24.4% ± 11.1%) and Freestyle (21.1% ± 16.7%), and between the two mechanical valve designs, Ultracor (19.3% ± 9.5%) and ATS (26.3% ± 10.8%), respectively. Conclusions Significant LV remodeling occurs early after AVR for aortic stenosis. The degree of regression in LV mass is independent of prosthesis type implanted.

Coronary flow reserve improves after aortic valve replacement for aortic stenosis: an adenosine transthoracic echocardiography study

OBJECTIVESThe goal of this study was to assess coronary flow reserve (CFR) before and after aortic valve replacement (AVR).BACKGROUNDCoronary flow reserve is impaired under conditions of left ventricular (LV) hypertrophy. It is not known whether CFR improves with regression of LV hypertrophy in humans.METHODSWe investigated 35 patients with pure aortic stenosis, LV hypertrophy and normal coronary arteriograms. Patients underwent adenosine transthoracic echocardiography on two occasions—immediately before AVR and six months postoperatively. Left ventricular mass, distal left anterior descending coronary artery (LAD) diameter, flow and CFR were assessed on each occasion.RESULTSDistal LAD diameter was successfully imaged in 30 patients (86%), and blood flow was successfully imaged in 27 (77%). Paired data were subsequently available in 24 patients, of whom 14 were men, mean age 68.1 ± 12.5 years, body mass index 24.5 ± 2.0 kg/m2, aortic valve gradient 93 ± 32 mm Hg. Pre- to post-AVR a significant decrease was seen in LV mass (271 ± 38 vs. 236 ± 32g, p < 0.01) and LV mass index (154 ± 21 vs. 134 ± 21g/m2, p < 0.01). Distal LAD diameter fell from 2.27 ± 0.37 to 2.23 ± 0.35 mm, p = 0.08). Pre- to post-AVR there was no significant change in resting parameters of peak diastolic velocity (0.43 ± 0.16 vs. 0.41 ± 0.11 m/s), distal LAD flow 23.3 ± 10.1 vs. 20.9 ± 5.2 ml/min or distal LAD flow scaled for LV mass (8.7 ± 3.8 vs. 9.0 ± 2.5 ml/min/100 g LV mass), but there was significant increase in hyperemic peak diastolic velocity (0.71 ± 0.26 vs. 1.08 ± 0.24 m/s; p < 0.01), distal LAD flow (37.8 ± 11.3 vs. 53.5 ± 16.1 ml/min; p < 0.01) and distal LAD flow scaled for LV mass (14.3 ± 5.0 vs. 23.3 ± 8.5 ml/min/100 g LV mass; p < 0.01). Coronary flow reserve, therefore, increased from 1.76 ± 0.5 to 2.61 ± 0.7.CONCLUSIONSCoronary flow reserve increases after AVR for aortic stenosis. This increase occurs in tandem with regression of LV hypertrophy.

M-Mode Echocardiography in Aortic Stenosis: Clinical Correlates and Prognostic Significance after Valve Replacement

To relate preoperative findings at M-mode echocardiography to preoperative clinical and haemodynamic status and to identify possible echocardiographic risk factors for mortality after aortic valve replacement (AVR), 250 patients with AVR for aortic stenosis (AS) were studied. In follow-up averaging 3.2 years there were 22 early (<30 days) and 23 late deaths. Rising NYHA function class and cardiothoracic index, and left ventricular (LV) failure were related to rising LV end-diastolic and end-systolic diameter index (EDDI, ESDI), and to increasing LV muscle mass index and decreasing fractional shortening (FS). High peak-to-peak systolic aortic valve gradient and LV end-systolic pressure were related to small dimensions of LV with increased FS and posterior wall thickness (PWTh). EDDI ≤20 mm/m2 and increasing PWTh were independent risk factors for early mortality. Patients with EDDI ≤20mm/m2 had normal or supranormal FS. PWTh was the only independent risk factor in long-term survival: 5-year rates being 81 ± 6%, 94 ± 3% and 85 ± 7% for PWTh < 13, 14–17 and ≥18 mm, respectively (p = 0.03). Prevalence of concomitant coronary artery disease (CAD) rose with decreasing PWTh. Angina pectoris in non-CAD patients was related to very high PWTh. Subnormal EDDI was associated with poor surgical outcome, and dilated, poorly contracting LV with congestive heart failure prior to AVR. The degree of LV hypertrophy seemed to be the dominant risk factor, but confounders included myocardial ischaemia due to CAD in low-grade hypertrophy or to hypertrophy per se. A hypofhetically confounding factor is the reversibility potential of moderate or severe LV hypertrophy following AVR.