Preclinical models of cardiotoxicity from immune checkpoint inhibitor therapy.

Immune checkpoint inhibitor (ICI) therapy represents a ground-breaking paradigm in cancer treatment, harnessing the immune system to combat malignancies by targeting checkpoints such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1). The use of ICI therapy generates distinctive immune-related adverse events (irAEs) including cardiovascular toxicity, necessitating targeted research efforts. This comprehensive review explores preclinical models dedicated to ICI-mediated cardiovascular complications including myocarditis. Tailored preclinical models of ICI-mediated myocardial toxicities highlight the key role of CD8+ T cells, emphasizing the profound impact of immune checkpoints on maintaining cardiac integrity. Cytokines and macrophages were identified as possible driving factors in disease progression, and at the same time, initial data on possible cardiac antigens responsible are emerging. The implications of contributing factors including thoracic radiation, autoimmune disorder, and the presence of cancer itself are increasingly understood. Besides myocarditis, mouse models unveiled an accelerated progression of atherosclerosis, adding another layer for a thorough understanding of the diverse processes involving cardiovascular immune checkpoint signalling. This review aims to discuss current preclinical models of ICI cardiotoxicity and their potential for improving enhanced risk assessment and diagnostics, offering potential targets for innovative cardioprotective strategies. Lessons from ICI therapy can drive novel approaches in cardiovascular research, extending insights to areas such as myocardial infarction and heart failure.

Detectable troponin below the 99th percentile predicts survival in patients undergoing coronary angiography.

Background: Cardiac troponin I (cTnI) above the 99th percentile is associated with an increased risk of major adverse events. Patients with detectable cTnI below the 99th percentile are a heterogeneous group with a less well-defined risk profile. The purpose of this study is to investigate the prognostic relevance of detectable cTnI below the 99th percentile in patients undergoing coronary angiography. Methods: The study included 14,776 consecutive patients (mean age of 65.4 ± 12.7 years, 71.3 % male) from the Essen Coronary Artery Disease (ECAD) registry. Patients with cTnI levels above the 99th percentile and patients with ST-segment elevation acute myocardial infarction were excluded. All-cause mortality was defined as the primary endpoint. Results: Detectable cTnI below the 99th percentile was present in 2811 (19.0 %) patients, while 11,965 (81.0 %) patients were below detection limit of the employed assay. The mean follow-up was 4.25 ± 3.76 years. All-cause mortality was 20.8 % for patients with detectable cTnI below the 99th percentile and 15.0 % for those without detectable cTnI. In a multivariable Cox regression analysis, detectable cTnI was independently associated with all-cause mortality with a hazard ratio of 1.60 (95 % CI 1.45-1.76; p < 0.001). There was a stepwise relationship with increasing all-cause mortality and tertiles of detectable cTnI levels with hazard ratios of 1.63 (95 % CI 1.39-1.90) for the first tertile to 2.02 (95 % CI 1.74-2.35) for the third tertile. Conclusions: Detectable cTnI below the 99th percentile is an independent predictor of mortality in patients undergoing coronary angiography with the risk of death growing progressively with increasing troponin levels.

Acute coronary occlusion with vs. without ST elevation: impact on procedural outcomes and long-term all-cause mortality.

BACKGROUND: Acute total occlusion (ATO) is diagnosed in a substantial proportion of patients with non-ST-elevation myocardial infarction (NSTEMI). We compared procedural outcomes and long-term mortality in patients with STEMI with NSTEMI with vs. without ATO. METHODS AND RESULTS: We included patients with acute myocardial infarction (AMI) undergoing invasive coronary angiography between 2004 and 2019 at our centre. Acute total occlusion was defined as thrombolysis in myocardial infarction (TIMI) 0-1 flow in the infarct-related artery or TIMI 2-3 flow with highly elevated peak troponin (>100-folds the upper reference limit). Association between presentation and long-term mortality was evaluated using multivariable adjusted Cox regression analysis. From 2269 AMI patients (mean age 66 ± 13.2 years, 74% male), 664 patients with STEMI and 1605 patients with NSTEMI (471 [29.3%] with ATO) were included. ATO(+)NSTEMI patients had a higher frequency of cardiogenic shock and no reflow than ATO(-)NSTEMI with similar rates compared with STEMI patients (cardiogenic shock: 2.76 vs. 0.27 vs. 2.86%, P < 0.0001, P = 1; no reflow: 4.03 vs. 0.18 vs. 3.17%, P < 0.0001, P = 0.54). ATO(+)NSTEMI and STEMI were associated with 60 and 55% increased incident mortality, respectively, as compared with ATO(-)NSTEMI (ATO(+)NSTEMI: 1.60 [1.27-2.02], P < 0.0001, STEMI: 1.55 [1.24-1.94], P < 0.0001). Likewise, left ventricular ejection fraction (48.5 ± 12.7 vs. 49.1±11 vs. 50.6 ± 11.8%, P = 0.5, P = 0.018) and global longitudinal strain (-15.2 ± -5.74 vs. -15.5 ± -4.84 vs. -16.3 ± -5.30%, P = 0.48, P = 0.016) in ATO(+)NSTEMI were comparable to STEMI but significantly worse than in ATO(-)NSTEMI. CONCLUSION: Non-ST-elevation myocardial infarction patients with ATO have unfavourable procedural outcomes, resulting in increased long-term mortality, resembling STEMI. Our findings suggest that the occlusion perspective provides a more appropriate classification of AMI than differentiation into STEMI vs. NSTEMI.

BNP and NT-proBNP Thresholds for the Assessment of Prognosis in Patients Without Heart Failure.

Background: Brain natriuretic peptide (BNP)/N-terminal-pro hormone brain natriuretic peptides (NT-proBNP) enable risk stratification, diagnosing, and monitoring of heart failure patients. An additional prognostic value for BNP/NT-proBNP in nonheart failure patients and general population cohorts is described in the literature, but specific cut-off levels are only described for heart failure patients. Objectives: This study aimed to determine thresholds for risk stratification in nonheart failure patients. Methods: Based on the Essen Coronary Artery Disease registry we excluded patients with known heart failure or elevated BNP/NT-pro BNP levels. The resulting cohort was divided into a derivation and validation cohort using random sampling. The prognostic value of BNP/NT-proBNP of incident mortality was evaluated in the derivation cohort using univariate and multivariable cox regression analysis. In receiver operating characteristic analysis and corresponding area under the curve the optimal threshold was determined using Youdens J index. The findings were verified in the validation cohort. Results: A total of 3,690 patients (age 62.9 ± 12.5 years, 71% male, 68% patients with coronary artery disease) were included. During a mean follow-up of 2.6 ± 3.4 years (median 1.2 [IQR: 0.4-2.88]), 169 deaths of any cause occurred. Based on Youden's J index, BNP-thresholds of 9.6 and 29pg/ml and NT-proBNP thresholds of 65 and 77pg/ml for men and women, respectively, were determined. BNP/NT-proBNP levels above these thresholds were associated with increased mortality in the derivation cohort (HR: 2.44 [95% CI: 1.32-4.53], P = 0.005). The predictive value was confirmed in the validation cohort (HR: 2.78 [95% CI: 1.26-6.14], P = 0.01). Conclusions: We here describe sex-specific BNP/NT-proBNP thresholds that allow prediction of impaired survival in patients without heart failure, independent of traditional cardiovascular risk factors.

The degree of permanent pacemaker dependence and clinical outcomes following transcatheter aortic valve implantation: implications for procedural technique.

Aims: Conduction abnormalities necessitating permanent pacemaker (PPM) implantation remain the most frequent complication post-transcatheter aortic valve implantation (TAVI), yet reliance on PPM function varies. We evaluated the association of right-ventricular (RV)-stimulation rate post-TAVI with 1-year major adverse cardiovascular events (MACE) (all-cause mortality and heart failure hospitalization). Methods and results: This retrospective cohort study of patients undergoing TAVI in two high-volume centers included patients with existing PPM pre-TAVI or new PPM post-TAVI. There was a bimodal distribution of RV-stimulation rates stratifying patients into two groups of either low [≤10%: 1.0 (0.0, 3.6)] or high [>10%: 96.0 (54.0, 99.9)] RV-stimulation rate post-TAVI. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated comparing MACE in patients with high vs. low RV-stimulation rates post-TAVI. Of 4659 patients, 408 patients (8.6%) had an existing PPM pre-TAVI and 361 patients (7.7%) underwent PPM implantation post-TAVI. Mean age was 82.3 ± 8.1 years, 39% were women. A high RV-stimulation rate (>10%) development post-TAVI is associated with a two-fold increased risk for MACE [1.97 (1.20, 3.25), P = 0.008]. Valve implantation depth was an independent predictor of high RV-stimulation rate [odds ratio (95% CI): 1.58 (1.21, 2.06), P=<0.001] and itself associated with MACE [1.27 (1.00, 1.59), P = 0.047]. Conclusion: Greater RV-stimulation rates post-TAVI correlate with increased 1-year MACE in patients with new PPM post-TAVI or in those with existing PPM but low RV-stimulation rates pre-TAVI. A shallower valve implantation depth reduces the risk of greater RV-stimulation rates post-TAVI, correlating with improved patient outcomes. These data highlight the importance of a meticulous implant technique even in TAVI recipients with pre-existing PPMs.