Canadian Cardiology Today

Pushing the Envelope for Transcatheter Valve Interventions in Canada

2025-09-29T15:16:33+00:00

Transcatheter valve interventions (TVIs) have revolutionized the treatment of structural heart disease, by providing a less invasive option to surgical valve repair or replacement for patients. Canada has been at the forefront of adopting these therapies, yet significant challenges remain. These include expanding indications, training operators, optimizing access, and integrating these rapidly evolving procedures into a government-funded single-access healthcare system. This review explores the current landscape of TVIs in Canada. We discuss the necessity for centres of excellence, training pathways for operators, and the multidisciplinary infrastructure required to ensure equitable and high-quality care.

Role and Indications for Device Therapies in Heart Failure: Condensed Summary

2025-09-29T15:16:32+00:00

Over the past decade, the substantial benefits associated with current guideline-directed medical therapy for heart failure with reduced ejection fraction (HFrEF) have been brought into the light, as emphasized in a recent publication from our institution.Despite these advances, device therapy continues to hold an important place in treating heart failure (HF), both for left ventricular (LV) remodeling (and associated prognosis) as well as for preventing sudden cardiac death (SCD).

Cardiac resynchronization therapy (CRT) is a key intervention in heart failure (HF) management, particularly for patients with left bundle branch block (LBBB), which is observed in 15–25% of patients with HF, and is associated with reduced left ventricular function. CRT helps in correcting dyssynchronous ventricular contraction leading to impaired cardiac output. Although less prevalent, right bundle branch block (RBBB) and nonspecific interventricular conduction delay (IVCD) are also associated with adverse remodelling, including increased right ventricular volumes and reduced function.

Contemporary Management of Heart Failure with Preserved Ejection Fraction: What is Current and What Lies Ahead?

2025-09-29T15:16:31+00:00

In Canada, the incidence of heart failure (HF) among adults ≥40 years has increased from 521 per 100,000 to 601 per 100,000 from 2013 to 2023, and is expected to rise further in the coming decades. HF is the second leading cause of death in Canada, with an age standardized all-cause mortality rate of 5,761 per 100,000 compared to people without HF at 913 per 100,000. HF with preserved ejection fraction (HFpEF), defined as the clinical syndrome of HF with left-ventricular ejection fraction (LVEF) ≥50%, comprises approximately half of all HF diagnoses. Contemporary data published this year suggests one- and five-year mortality rates for HFpEF are similar to those seen in heart failure with reduced ejection fraction (HFrEF).

The Canadian Cardiovascular Society (CCS) endorses the universal definition of HF, which classifies HFpEF as having an LVEF cutoff of 50% and emphasizes markers of increased left ventricular (LV) filling pressures as a reflection of the underlying pathophysiology. HFpEF is associated with both functional and structural cardiac abnormalities, including diastolic dysfunction, ventricular and atrial remodelling, LV hypertrophy, and fibrosis.⁵ In addition, systemic inflammation, endothelial dysfunction, altered myocardial energetics, and abnormalities in skeletal muscle are increasingly recognized as important contributors to HFpEF pathophysiology and serve as therapeutic targets.

Comorbid conditions including type 2 diabetes mellitus (T2DM), obesity, atrial fibrillation, chronic kidney disease, pulmonary hypertension, obstructive sleep apnea, and iron deficiency have been associated with the development and progression of HFpEF. Furthermore, there is growing interest in identifying distinct HFpEF phenotypes to better characterize patient populations beyond their comorbid conditions, with the aim of personalizing prognosis and treatment options. In a recent study, three distinct HFpEF phenotypes were identified, including a younger group with primarily New York Heart Association (NYHA) II symptoms, a higher prevalence of smoking, and a lower prevalence of diabetes and chronic kidney disease; another consisting of older age individuals (mean age 77 years), predominantly women with atrial fibrillation and chronic kidney disease; and a third group of intermediate age (mean age 66 years) with a very high prevalence of obesity and diabetes, greater functional impairment, and elevated inflammatory markers. Notably, the patients in this latter phenotype, with a very high prevalence of obesity and diabetes, were most likely to be hospitalized for HF along with having an overall mortality risk comparable to those patients classified in the older, atrial fibrillation, chronic kidney disease phenotype, despite their younger age.

Secondary Prevention After Myocardial Infarction: Bridging Evidence to Practice

2025-09-29T15:16:30+00:00

Management of acute coronary syndrome (ACS) has advanced significantly over the past years, with various strategies shown to improve patient survival and reduce cardiovascular (CV) adverse events. An expanding body of literature supports the efficacy of both pharmacologic and non-pharmacologic approaches after acute myocardial infarction (MI). This review aims to provide a comprehensive overview of the secondary prevention strategies after acute MI in the modern era, with a particular focus on recent guidelines and their application in Canadian healthcare practice.

Physiologic Pacing in 2025: Guidance Made Simple

2025-09-29T15:16:29+00:00

Conventional right ventricular pacing (RVP), particularly at the right ventricular apex, has long been the standard approach for ventricular pacing in patients requiring permanent pacemakers. However, RVP has been shown to introduce electrical and mechanical dyssynchrony, resulting in adverse remodelling, atrial fibrillation, and heart failure. The deleterious effects of a high RVP burden have been demonstrated in the MOST and DAVID trials, wherein patients with ventricular pacing >40% were identified as being at risk of increased adverse clinical outcomes, such as hospitalization for heart failure and death (hazard ratio [HR] 1.61; 95% confidence interval [CI] 1.06–2.44).

In patients with baseline ventricular systolic dysfunction and left bundle branch block or a high ventricular pacing burden, cardiac resynchronization therapy (CRT) using conventional biventricular pacing (BiVP) has been shown to be superior to RVP in preventing ventricular dilation, hospitalization for heart failure, and death. Both the BLOCK-HF trial, which compared BiVP to RV pacing in patients with a left ventricular ejection fraction (LVEF) ≤50% and a high pacing burden, and the MADIT-CRT trial, which compared implantable cardioverter-defibrillator therapy alone to CRT with defibrillator in patients with LVEF ≤30% and QRS duration ≥130ms, showed a reduction in all-cause mortality and heart failure events in the BiVP group (HR 0.74; 95% CI 0.60–0.90 and HR 0.66; 95% CI 0.52–0.84, respectively). However, approximately one-third of patients do not respond to conventional BiVP. Moreover, the benefits of conventional BiVP have not been consistently shown across all cohorts.

To overcome the detrimental effects of RVP and the limitations of conventional BiVP, conduction system pacing (CSP) was introduced. This approach harnesses the His-Purkinje system, thereby delivering stimulation mimicking native ventricular activation. The two primary CSP techniques, His bundle pacing (HBP) and left bundle branch area pacing (LBBAP), have demonstrated promise in improving both electrical synchrony and clinical outcomes.