Sam Dawkins

Background: Cardiac damage (CD) is prevalent across the spectrum of aortic stenosis (AS) and is a strong predictor of adverse outcomes. The natural history of CD in early AS and drivers of its progression, are poorly defined. We aimed to identify predictors and the prognostic significance of CD progression in patients with non-severe AS. Methods: This was a single centre cohort study with longitudinal follow-up. Patients with mild or moderate AS at baseline and over serial echocardiographic follow-up were evaluated for the presence and progression of CD over time. Results: 1751 patients were included. At baseline, CD was present in 1320 (75%), categorized as stage 1 in 231 (13%), stage 2 in 672 (38%), stage 3 in 109 (6%) and stage 4 in 308 (18%). Over a median follow-up of 2.1 [Q1–Q3 1.1-3.6] years, the prevalence of advanced-stage (stages 3 and 4) CD increased from 24% to 30%. Factors associated with progression to advanced-stage CD included comorbidity burden (adjusted OR [aOR] 1.23 per additional comorbidity; 95% CI: 1.10–1.38; p < 0.001) and the presence of atrial fibrillation (aOR 3.23; 95% CI: 1.15–9.07, p = 0.024) or left atrial dilation (aOR 1.55; 95% CI: 1.11–2.16, p = 0.010)], but not AS severity. Progression of CD was independently associated with all-cause mortality (adjusted HR [aHR] 1.35; 95% CI: 1.07–170; p = 0.012). Conclusions: In non-severe AS, CD is common and frequently progresses over time. CD progression appears to be driven by comorbidities and pre-existing myocardial remodelling and is an independent predictor of all-cause mortality.

Aims: Transcatheter mitral valve replacement (TMVR) has become a feasible alternative to surgical mitral valve replacement (SMVR) in selected patients at high surgical risk. The risk of valve thrombosis following SMVR and TMVR, and the optimal antithrombotic therapy following these procedures, remains uncertain. We aimed to compare the incidence of bioprosthetic mitral valve thrombosis (bMVT) after SMVR and TMVR, and the incidence of bMVT between patients on different antithrombotic regimens. Methods and results: A literature search of Medline, Embase, and Cochrane Library was performed between January 2000 and August 2024. Random-effects models were used to derive pooled estimates of the incidence of bMVT in the absence of prior or active endocarditis and valve thrombosis. A total of 47 studies (6170 patients, total follow-up 9541.8 patient-years) were eligible for inclusion. The overall incidence of bMVT was 5.05 [95% confidence interval (CI) 3.18–8.01, I2 = 82%] per 100-patient-years. Subclinical bMVT was more common than clinically significant bMVT: incidence 19.11 vs. 7.91 per 100-patient-years, adjusted incidence rate ratio (aIRR) 4.62 (95% CI 1.39–15.36), P = 0.012. bMVT was numerically more common after TMVR than SMVR, but the comparison was not statistically significant: incidence 7.03 vs. 0.58 per 100-patient-years, aIRR 2.19 (95% CI 0.72–6.72), P = 0.170. Patients on vitamin-K antagonists (VKA) had a lower incidence of bMVT than patients on direct oral anticoagulants (DOAC; incidence 5.72 vs. 17.08, aIRR 0.31, 95% CI 0.13–0.73, P = 0.007). Conclusions: bMVT is not uncommon, with numerically higher incidence in transcatheter compared to surgical valves, but the comparison was not statistically significant. VKAs are associated with a lower incidence of bMVT compared to DOACs.

Severe secondary mitral regurgitation carries a poor prognosis with one in five patients dying within 12 months of diagnosis. Fortunately, there are now a number of safe and effective therapies available to improve outcomes. Here, we summarise the most up-to-date treatments. Optimal guideline-directed medical therapy is the mainstay therapy and has been shown to reduce the severity of mitral regurgitation in 40–45% of patients. Rapid medication titration protocols reduce heart failure hospitalisation and facilitate earlier referral for device therapy. The pursuit of sinus rhythm in patients with atrial fibrillation has been shown to significantly reduce mitral regurgitation severity, as has the use of cardiac resynchronisation devices in patients who meet guideline-directed criteria. Finally, we highlight the key role of mitral valve intervention, particularly transcatheter edge-to-edge repair (TEER) for management of moderate-severe mitral regurgitation in carefully selected patients with poor left ventricular systolic function, with a number needed to treat of 3.1 to reduce heart failure hospitalisation and 5.9 to reduce all-cause death. To slow the rapid accumulation of morbidity and mortality, we advocate a proactive approach with accelerated medical optimisation, followed by management of atrial fibrillation and cardiac resynchronisation therapy if indicated, then, rapid referral to the Heart Team for consideration of mitral valve intervention in patients with ongoing symptoms and at least moderate-severe mitral regurgitation. Mitral TEER has been shown to be ‘reasonably cost-effective’ (but not cost-saving) in the UK in selected patients, although TEER remains underused with only 6.5 procedures per million population (pmp) compared with Germany (77 pmp), Switzerland (44 pmp) and the USA (32 pmp).

An 87-year-old male with background of hypertension and permanent atrial fibrillation presented after collapsing while watching cricket. He was peripherally cyanosed, with an oxygen saturation of 60% on 10 L/min oxygen. He did not report any chest pain. Blood pressure and heart rate were normal. Clinical examination was unremarkable, except for elevated jugular venous pressure. The electrocardiogram demonstrated sinus rhythm, with Q-waves and ST elevation in the inferior and septal leads (Panel A). Serum Troponin I was normal. The INR was in the low therapeutic range (2.0). A bedside echocardiogram revealed severely dilated right cardiac chambers with severe right ventricular (RV) systolic impairment and evidence of RV volume overload. There was a large atrial septal defect (ASD) with right-to-left flow and a hyperintense lesion at the right coronary artery (RCA) ostium (Panels B and C, Supplementary data online, Videos S1 and S 2 ). The computed tomography pulmonary angiogram showed an extensively calcified and proximally occluded RCA, with a large thrombus protruding from the ostium into the aorta (Panels D–G, Supplementary data online, Videos S3). Intervention for the thrombotic RCA occlusion was considered but this would have been immensely complex and the risk was felt to be too high. ASD closure was considered inappropriate given the severe RV systolic impairment and longstanding large shunt. The patient was therefore managed palliatively, treated with low molecular weight heparin, and died a few hours later. This is a rare case illustrating acute right-to-left cardiac shunt through a large ASD, after an RV infarction likely due to paradoxical embolus of the RCA.

Background: Transcatheter aortic valve implantation (TAVI) is usually planned using contrast-enhanced computed tomography (CT) to determine the suitability of cardiovascular anatomy. Computed tomography for TAVI planning requires the administration of intravenous contrast, which may not be desirable in patients with severely reduced renal function. Case summary: We present an unusual case of an 89-year-old patient with an urgent need for treatment of critical, symptomatic aortic stenosis who also had severe chronic kidney disease. We judged that this posed a relative contraindication to the use of intravenous contrast. We designed and implemented a novel, contrast-free cardiovascular magnetic resonance (CMR) protocol and used this to plan all aspects of the procedure. Transcatheter aortic valve implantation was conducted successfully with zero contrast medium administration leading to an excellent clinical result and recovery of renal function. Conclusion: Contrast-free CMR appears to be a viable alternative to CT for planning structural aortic valve intervention in the rare cases where intravenous contrast is relatively contraindicated.