Canadian Journal of Cardiology最新文献

Pathogenic genetic alterations are a well-recognized mechanism in cardiomyopathies. As such, genetic testing has become an integral component of the diagnostic pathway for cardiomyopathy. Subsequent developments in gene-specific therapies have advanced precision medicine by enabling direct targeting of pathogenic genetic variants, demonstrating promise as the ultimate therapy for cardiomyopathy. Gene therapy can be categorized into three main approaches: gene replacement, gene silencing, and direct genome editing. Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology laid the foundation for genome editing, followed by the development of base editors and prime editors. These tools allow for single-base changes to address point mutations, as well as target insertion, deletion, transition, and transverse mutations. There have been equally essential advancements in the development of gene delivery vectors. These include viral vectors, especially the novel capsids of adeno-associated virus, due to their lower immunogenicity and better transduction efficiency compared to other viral vectors; virus-like particles that contain self-assembling virus-derived structures without the genetic material; and non-viral nanoparticles that can be polymeric, inorganic, or, most commonly, lipid nanoparticles. Antisense oligonucleotides have also emerged as part of the toolkit to allow for exon skipping in large genes with pathogenic variants. All these gene therapy and delivery vector approaches come with their own advantages and safety considerations. In this review, we describe the genetic basis and expanding research on gene-based therapies for patients with hypertrophic cardiomyopathy, dilated cardiomyopathy, muscular dystrophy-related cardiomyopathies, and transthyretin amyloidosis.

Background: Clinical and angiographic outcomes following chronic total occlusion (CTO) percutaneous coronary intervention (PCI) remain incompletely investigated, whereas direct comparisons with non-CTO-PCI are missing. The present study aimed to compare the mid-term clinical and angiographic outcomes following successful CTO-PCI and non-CTO-PCI.

Methods: Consecutive patients from the Intracoronary Stenting and Angiographic Results - Chronic Total Occlusion (ISAR-CTO) Registry undergoing successful CTO recanalization as well as all successful non-CTO-PCI procedures from our institutional database were included. Propensity score matching (PSM) with a 1:3 matching ratio was performed. The primary endpoint was the incidence of major adverse cardiac events (MACE) at 12-month follow-up. The secondary angiographic endpoint was in-segment binary restenosis at surveillance angiography.

Results: Overall, 453 CTO-PCI patients (472 lesions) and 14733 non-CTO-PCI patients (23458 lesions) were analyzed. After PSM, a total of 1812 patients were included in the present study [CTO-PCI, n=453 patients (472 lesions); non-CTO-PCI, n=1359 patients (1424 lesions)]. There were no significant differences in terms of MACE (adjusted hazard ratio [HR_adj]=1.26, 95% confidence interval [CI] 0.95-1.66) between CTO-PCI and non-CTO-PCI at 12-month follow-up. CTO-PCI independently correlated with a higher risk of target lesion revascularization (TLR) (HR_adj=1.66, 95%CI [1.21-2.27]) and a significantly lower risk of MI (HR_adj=0.231; 95%CI [0.06-0.98]). CTO-PCI independently correlated with the occurrence of binary restenosis (adjusted odds ratio [OR_adj]=1.86, 95%CI [1.38-2.51]) at surveillance angiography.

Conclusions: CTO-PCI was independently associated with significantly higher rates of TLR as well as a significantly lower incidence of MI at 12-months follow-up. QCA analysis of surveillance angiography showed superior angiographic outcomes following non-CTO-PCI.

While large randomized trials have failed to demonstrate a clinical benefit from conventional aspiration thrombectomy (1), i nnovative strategies remain needed, particularly in patients with a large thrombus burden. We report the case of a patient presenting with a late inferior myocardial infarction and a massive, organized thrombus in the right coronary artery (RCA), requiring the combination of two thrombectomy techniques to restore coronary flow.

Background: Right ventricular free-wall longitudinal strain (RVFWLS) is a sensitive marker of RV dysfunction after heart transplantation (HT), and automated RVFWLS may improve efficiency. This study evaluated the accuracy and prognostic value of automated echocardiographic RVFWLS using cardiac magnetic resonance (CMR) as reference.

Methods: 150 HT recipients undergoing echocardiography and CMR within 3 days were retrospectively analyzed. The accuracy and prognostic value of fully- and semi-automated RVFWLS were compared with CMR. Image quality was graded as "optimal" or "acceptable" to assess its influence on automated measurements.

Results: Both fully- and semi-automated methods correlated with CMR (r = 0.727 and 0.863; P < 0.001), with the semi-automated approach showing smaller bias, narrower limits of agreement, and lower coefficient of variation. The subgroup of "acceptable" image quality reduced the accuracy of automated RVFWLS. During a median 37-month follow-up, 29 patients experienced adverse events. In multivariable Cox analysis, semi-automated RVFWLS (HR = 1.499; AIC = 229, C-index = 0.807) showed comparable prognostic performance to CMR (HR = 1.570; AIC = 216, C-index = 0.852) and outperformed fully-automated RVFWLS (HR = 1.284; AIC = 249, C-index = 0.734). ROC analysis confirmed superior predictive ability of fully- and semi-automated RVFWLS for adverse events (AUC 0.845 vs 0.735, P = 0.002).

Conclusions: Automated RVFWLS showed good accuracy and prognostic value in HT patients validated by CMR. The semi-automated approach may be preferable for post-HT follow-up due to its superior performance, whereas the fully-automated method may be a potentially acceptable alternative when image quality is adequate.