Myocardial injury following transcatheter aortic valve implantation: insights from delayed-enhancement cardiovascular magnetic resonance

Abstract

Aims: The aim of this study was to evaluate the presence, localisation and extent of myocardial injury as determined by late gadolinium enhancement (LGE) on cardiovascular magnetic resonance (CMR) imaging in patients undergoing transcatheter aortic valve implantation (TAVI). Methods and results:A total of 37 patients, who underwent successful TAVI with a balloon-expandable valve (transapical [TA], n=11; non-TA, n=26), were included. Cardiac biomarker (CK-MB and cTnT) levels were determined at baseline and following TAVI. CMR was performed within a week before and within 30 days following TAVI. Some increase in cardiac biomarkers was detected in 97% of the patients as determined by a rise in cTnT, and in 49% of the patients as determined by a rise in CK-MB. Following TAVI, no new myocardial necrosis defects were observed with the non-TA approach. Nonetheless, all patients who underwent TAVI through the TA approach had new focal myocardial necrosis in the apex, with a median myocardial extent and necrotic mass of 5% [2.0-7.0] and 3.5 g [2.3-4.5], respectively.Conclusions: Although some increase in cardiac biomarkers of myocardial injury was systematically detected following TAVI, new myocardial necrosis as evaluated by CMR was observed only in patients undergoing the procedure through the TA approach, involving ~5% of the myocardium in the apex. KEYWORDS• cardiac biomarkers • cardiac magnetic resonance imaging • late gadolinium enhancement • myocardial injury • transcatheter aortic valve implantation

Post‐Procedural Troponin Elevation and Clinical Outcomes Following Transcatheter Aortic Valve Implantation

“…Third, the mechanisms responsible for the association of cTnT elevation with subsequent outcomes cannot be fully elucidated in this clinical observational study; dedicated mechanistic studies are more suited to address this issue. 23,24,32 Conclusions VARC-2-defined cTnT elevation emerged as an independent predictor of 30-day mortality and remained a modest, but significant, predictor of 2-year mortality post-TAVI. Presence of troponin elevation appears to be prognostically relevant, whereas absence of myocardial injury does not preclude an adverse prognosis, as reflected by a reasonably high specificity but low sensitivity.…”

“…Second, cTnT was not measured at prespecified time points postintervention; however, cTnT was measured in all patients at 12 hours and again at 24 hours and later in case of increased 12‐hour values (ie, in 96.2% of patients); hence, it is unlikely that peak cTnT values were not recorded in this population. Third, the mechanisms responsible for the association of cTnT elevation with subsequent outcomes cannot be fully elucidated in this clinical observational study; dedicated mechanistic studies are more suited to address this issue 23, 24, 32…”

“…First, direct myocardial damage is induced by mechanical compression of the left ventricular outflow tract during balloon dilatation and valve implantation and—to a greater extent—by myocardial puncture during transapical interventions. Second, some,23 but not all, mechanistic studies employing magnetic resonance imaging24 pointed to the primary role of distal embolization of calcium microparticles into the coronaries during valvuloplasty and prosthesis implantation—a mechanism that is consistent with preclinical evidence25 as well as evidence of cerebrovascular microemboli post‐TAVI 26. Third, temporary hypotension during rapid pacing or balloon predilatation, excessive bradycardia because of conduction abnormalities, or, conversely, tachycardia in the setting of inotropic hemodynamic support can result in myocardial ischemia attributed to hypoperfusion of the typically hypertrophic myocardium.…”

Remote Ischemic Preconditioning Neither Improves Survival nor Reduces Myocardial or Kidney Injury in Patients Undergoing Transcatheter Aortic Valve Implantation (TAVI)

“…However, myocardial injury occurs frequently in patients receiving TAVI, which is associated with worse outcome [13,14]. It can be caused by several conditions [14,15] including (1) micro-embolism into coronaries, (2) hypoperfusion due to rapid pacing, (3) direct mechanical myocardial injury due to balloon dilatation and prosthesis implantation, and (4) possible complications during the procedure. Moreover, acute kidney injury (AKIN) is regularly observed as a complication following TAVI, being partly related to the amount of injected iodine contrast agent during the procedure.…”

Initial Experience of Transcatheter Mitral Valve Replacement With a Novel Transcatheter Mitral Valve

“…Besides the importance of noncardiac comorbidities, the presence of an LVEF <20% may be associated with further reduction of the LVEF after the procedure (23,24), leading to persistent heart failure and death. In addition, the myocardial injury associated with the transapical approach may further contribute to decreased LVEF(25). All patients included in our small series had an LVEF of 25% to 30%, and none of them experienced decompensated heart failure after the procedure.…”