Prevention of valve prosthesis--patient mismatch before aortic valve replacement: does it matter and is it feasible?

Can Perceval sutureless valve reduce the rate of patient-prosthesis mismatch?†

OBJECTIVES

The aim of this study is to compare the theoretical incidence of patient-prosthesis mismatch (PPM) in patients undergoing a sutureless or a sutured aortic valve replacement using an exact statistical matching.

METHODS

Between May 2012 and March 2016, 65 patients with severe symptomatic aortic stenosis underwent a sutureless aortic valve replacement with the Perceval bioprosthesis in 2 centres. Moreover, 177 aortic valve replacements with conventional sutured bioprosthesis were performed between August 2003 and September 2015. Perceval and sutured patients were 1:1 exactly matched for sex and body surface area (BSA), resulting in 62 couples (sutureless: BSA 1.77 ± 0.16 m 2 , female 62.9% vs sutured: BSA 1.77 ± 0.15 m 2 , female 62.9%).

RESULTS

After matching, the indexed effective orifice area was 1.50 ± 0.18 cm 2 /m 2 and 0.81 ± 0.19 cm 2 /m 2 in the sutureless and the sutured group, respectively ( P  < 0.001). No PPM occurred in patients who received a Perceval bioprosthesis ( n  = 62). In the sutured group ( n  = 62), 38 patients (61.3%) developed a PPM, which was moderate in 41.9% ( n  = 26) and severe in 19.4% ( n  = 12) ( P  < 0.001).

CONCLUSIONS

The indexed effective orifice area of the sutureless group was significantly larger than in the sutured one. The incidence of PPM with the conventional sutured biprosthesis was 61.3%, while it decreases to 0% in the sutureless group. No PPM was reported in the sutureless valve group. Therefore, the Perceval sutureless valve provides larger effective orifice areas compared to the sutured conventional bioprosthesis and could be considered as a good option to reduce the risk of a PPM.

Comparison of balloon-expandable versus self-expandable valves for transcatheter aortic valve implantation in patients with low-gradient severe aortic stenosis and preserved left ventricular ejection fraction

A relevant proportion of patients, classified as severe aortic stenosis on the basis of valve area ≤1 cm(2), have a mean transvalvular gradient ≤40 mm Hg, despite a preserved left ventricular ejection fraction (LGSAS). We assessed the clinical and hemodynamic impact of transcatheter aortic valve implantation in patients with symptomatic LGSAS at high risk for surgery or inoperable, according to the type of percutaneous valve implanted. Ninety-five patients received an Edwards SAPIEN valve (Edwards Lifesciences, Irvine, California) and 51 received a Medtronic CoreValve (Medtronic, Inc., Minneapolis, Minnesota). The hemodynamic performance of the 2 valves was similar in term of final transvalvular gradients (10 mm Hg, p = 0.069). Early mortality rate was 7% and was not different between the 2 valves (p = 0.73). During follow-up, cardiovascular mortality rate was similar between groups, and valve type was not a predictor of outcome (p = 0.72). Estimated survival by Kaplan-Meier at 2 years was 70%. At multivariate analysis, life-threatening or major bleeding, postprocedural aortic insufficiency, and acute kidney injury were the major predictors of an adverse outcome. In patients with LGSAS treated by transcatheter aortic valve implantation, the use of balloon-expandable versus self-expandable valves resulted in similar hemodynamic, early, and long-term clinical outcomes.

Aortic valve annular dimension in Indian population

AIM

The Aortic Valve (AV) annular dimension with respect to the Body Surface Area (BSA) of the Indian population is compared against the standard values. Presence of discrepancies can lead to patient prosthesis mismatch during aortic valve replacement surgeries.

METHODS

This study was conducted on 406 subjects. AV diameter was examined by using parasternal long axis view, where the imaging plane transects the AV in an anteroposterior direction and its x axis is aligned parallel to the long axis of aorta. Data were statistically analysed with western population.

RESULTS

The AV dimension ranged from 12.2 mm to 21.2 mm in the BSA range of 0.6 to 1.9 m(2), showing a linear increase in diameter with increasing BSA. There was an increase of about 2 mm, from 0.61 - 0.7 m(2) BSA to 0.71 - 0.8 m(2) BSA. A linear increase which ranged from 0.3 to 1 mm was observed for BSA which ranged from 0.81 m(2) to 1.2 m(2). In the BSA range of 1.21 - 1.3 m(2), there was an increase of 1.5 mm. A steady increase which ranged from 0.4-1 mm was observed in the BSA which ranged from 1.31- 1.9 m(2).

CONCLUSIONS

There is a significant difference between Indian and western population in the aortic dimension, in the body surface ranges of 0.61-0.7, 1.11-1.2, 1.21-1.3, 1.51-1.6, 1.61-1.7, 1.71-1.8 and 1.8-1.9 m(2). In the range of 1.21-1.3 m(2), the diameter was larger than standard, whereas in all the other ranges, AV diameter was smaller than standard values. BSA, as a good predictor of AV dimension, has also been proved.

Flow acceleration time and ratio of acceleration time to ejection time for prosthetic aortic valve function

OBJECTIVES

We sought to evaluate whether ejection dynamics, particularly acceleration time (AT) and the ratio of AT to ejection time (ET), can differentiate prosthetic aortic valve (PAV) stenosis from controls and prosthesis-patient mismatch (PPM).

BACKGROUND

Diagnosing PAV stenosis, especially in mechanical valves, may be challenging and has significant clinical implications.

METHODS

Doppler echocardiography was quantitated in 88 patients with PAV (44 mechanical and 44 bioprosthetic; age 63 ± 16 years; valve size range 18 to 25 mm) of whom 22 patients had documented PAV stenosis, 22 had PPM, and 44 served as controls. Quantitative Doppler parameters included ejection dynamics (AT, ET, and AT/ET) and conventional PAV parameters.

RESULTS

Patients with PAV stenosis had significantly lower effective orifice area (EOA) values and higher gradients compared with controls and PPM. Flow ejection parameters (AT and AT/ET) were significantly longer in the stenotic valves compared with PPM and controls (respective values for AT: 120 ± 24 ms, 89 ± 16 ms, and 71 ± 15 ms; for AT/ET: 0.4, 0.32, and 0.3, p ≤ 0.001). Patients with PPM had gradients and ejection dynamics that were intermediate between normal and stenotic valves. Receiver-operator characteristic (ROC) curve analysis showed that AT and AT/ET discriminated PAV stenosis from PPM and controls (area under ROC curve = 0.92 and 0.88, respectively). Combining AT with the conventional Doppler velocity index gave the highest area under the curve of 0.98 but was not statistically different from that of AT alone (p = 0.12). A cutoff of AT = 100 ms had a sensitivity and specificity of 86% for identifying PAV stenosis; for an AT/ET = 0.37, the sensitivity and specificity were 96% and 82%, respectively. Analysis by valve type (mechanical and biological) revealed similar results; however, biological valves had slightly higher areas under the curve for all systolic time intervals.

CONCLUSIONS

Ejection dynamics through PAV, particularly AT and AT/ET, are reliable angle-independent parameters that can help evaluate valve function and identify PAV stenosis.

Diagnostic evaluation of left-sided prosthetic heart valve dysfunction

Prosthetic heart valve (PHV) dysfunction is a rare, but potentially life-threatening, complication. In clinical practice, PHV dysfunction poses a diagnostic dilemma. Echocardiography and fluoroscopy are the imaging techniques of choice and are routinely used in daily practice. However, these techniques sometimes fail to determine the specific cause of PHV dysfunction, which is crucial to the selection of the appropriate treatment strategy. Multidetector-row CT (MDCT) can be of additional value in diagnosing the specific cause of PHV dysfunction and provides valuable complimentary information for surgical planning in case of reoperation. Cardiac magnetic resonance imaging (CMR) has limited value in the evaluation of biological PHV dysfunction. In this Review, we discuss the use of established imaging modalities for the detection of left-sided mechanical and biological PHV dysfunction and discuss the complementary role of MDCT in this context.

New concepts in valvular hemodynamics: implications for diagnosis and treatment of aortic stenosis

Aortic valve stenosis (AS) is the third-most frequent heart disease after coronary artery disease and arterial hypertension, and it is associated with a high incidence of adverse outcomes. Recent data support the notion that AS is not an isolated disease uniquely limited to the valve. Indeed, AS is frequently associated with abnormalities of the systemic arterial system, and, in particular, with reduced arterial compliance, which may have important consequences for the pathophysiology and clinical outcome of this disease. Moreover, AS may also be associated with left ventricular systolic dysfunction and reduced transvalvular flow rate, which pose important challenges with regards to diagnostic evaluation and clinical decision making in AS patients. Hence, the assessment of AS severity, as well as its therapeutic management, should be conducted with the use of a comprehensive evaluation that includes not only the aortic valve, but also the systemic arterial system and the left ventricle because these three entities are tightly coupled from both a pathophysiological and a hemodynamic standpoint.