Prosthesis-Patient Mismatch After “High-Risk” Aortic Valve Replacement

Abstract

S ince the initial description of prosthesispatient mismatch (PPM) more than 3 decades ago (1), the clinical import of PPM after surgical aortic valve replacement (SAVR) has been debated in the surgical published data. The phenotypic manifestation of PPM is an elevated aortic valve gradient after valve implantation. Although a number of indices have been used to characterize the frequency of PPM after valve replacement, the most common parameter used to describe its magnitude is the effective orifice area index (EOAi), which accounts for the body surface area (BSA) and, presumptively, the cardiac output. PPM is defined as moderate when the EOAi is #0.85 cm 2 /m 2 but $0.65 cm 2 /m 2 , and severe when the EOAi is <0.65 cm 2 /m 2 .PPM has been associated with higher early (2-5) and late mortality (4,6-10) after aortic valve surgery. In a meta-analysis comprising 34 studies that included 27,186 patients and 133,141 patient-years, both moderate and severe PPM increased all-cause mortality (hazard ratio: 1.19 and 1.84, respectively) and cardiac-related mortality (hazard ratio: 1.32 and 6.46, respectively); these relationships were consistent over time (11). The impact of PPM on late mortality may be influenced by the presence of older age, left ventricular (LV) dysfunction, New York Heart Association functional class III or IV symptoms, and concomitant coronary artery bypass grafting (12,13). PPM has been associated with a number of other untoward outcomes, including longer time in the intensive care unit (3); a reduction in functional improvement and exercise capacity (14,15); less regression of LV mass after valve surgery (16,17), particularly in patients with LV hypertrophy (18); increased neurologic events (19); and more late structural valve deterioration (20). PPM may have an even more profound impact on outcomes in patients with low gradient aortic stenosis (21,22). PPM was independently associated with increased rates of congestive heart failure, impaired LV mass regression, and a trend toward increased late mortality in patients with low gradient aortic stenosis (22). Transcatheter aortic valve replacement (TAVR) has provided another option for reducing PPM in patients undergoing aortic valve replacement because of the lower profile of the transcatheter valve without a sewing ring (23). A matched analysis of patients with aortic stenosis compared 50 patients treated using a balloon-expandable transcatheter valve with 2 groups of 50 patients who underwent surgery with a stented valve (Edwards Perimount Magna, Edwards Lifesciences Corp., Irvine, California) or a stentless valve (Medtronic Freestyle, Medtronic Inc., Minneapolis, Minnesota) (23). The mean transprosthetic gradient at discharge was lower in the TAVR group (10 AE 4 mm Hg) comparedwith the stented (13 AE 5 mm Hg) and stentless (14 AE 6 mm Hg) surgical groups. The incidence of severe PPM was significantly lower in the TAVR group (6%) than in the stented (28%) or stentless (20%) surgical groups, albeit with a higher rate of moderate paravalvular regurg...

Early and mid-term haemodynamic performance and clinical outcomes of St. Jude Medical Trifecta™ valve

“…PPM has been associated with worse outcomes after AVR surgery (22), as manifest by increased all-cause and cardiac-related mortality (23), longer stay in the intensive care unit (24), less regression of left ventricle mass (25) and more neurologic events (26). It is also an independent predictor of SVD (27).…”

Incidence, Predictors and Outcome of Prosthesis-Patient Mismatch after Transcatheter Aortic Valve Replacement: a Systematic Review and Meta-analysis

“…Additionally, the incidence of PPM was significant lower after TAVR in patients with smaller native aortic annulus (<20 mm) 11 , 16 , 39 but not in patients with larger aortic annulus (≥20 mm) 39 . This difference may be explained by a less frequent occupation of native aortic annulus due to absence of sewing ring 11 , 40 which resulted in better hemodynamic results 21 , 41 . Furthermore, patients underwent SAVR always have more selected size of valve, while patients underwent TAVR have limited size of valve.…”

“…This is in contrast to established data from the surgical literature, with moderate and severe PPM following SAVR shown to have a higher mortality in pooled data from 34 and 58 studies recruiting 27,186 and 40,381 patients respectively 5 , 6 . This paradox may be related to the influence of individual preoperative characteristics and baseline comorbidities 38 , 40 . Patients undergoing TAVR thus far have been older than that of SAVR, potentially with lower basic activity requirements, and multiple comorbidities that compete with the influence of PPM.…”