International Journal of Cardiology

International Journal of Cardiology | Vol. 10, No. 4, April 2019 | pp. 25–32

DOI: 10.46882/2019/IJC/000121

Original Research Article

The Role of Cardiovascular Magnetic Resonance Native T1 Mapping in the Early Detection of Anthracycline-Induced Cardiotoxicity

Emily C. Thorne¹, William H. Edwards²

¹Department of Cardio-Oncology, Royal Marsden Hospital, London, United Kingdom

²Division of Cardiology, Edinburgh Heart Centre, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom

Abstract:
Early identification of anthracycline-induced cardiotoxicity is critical to prevent irreversible heart failure in cancer survivors. While global longitudinal strain can reveal subclinical mechanical impairment, it reflects macroscopic alterations. This study investigated whether non-invasive cardiac magnetic resonance (CMR) native T1 mapping can detect earlier microstructural diffuse myocardial injury before structural deformation occurs. We prospectively followed 95 breast cancer and lymphoma patients undergoing doxorubicin-based chemotherapy regimens (cumulative dose greater than or equal to 240 mg/m²). Baseline and serial 3-month CMR imaging sessions quantified native T1 values and extracellular volume (ECV) fractions. Left ventricular ejection fraction (LVEF) was tracked simultaneously. Cardiotoxicity was defined as an absolute LVEF decline greater than 10% or a drop below 50% at 12 months. Cardiotoxicity developed in 18 patients (18.9%) at 12 months. In these patients, native T1 values increased significantly from baseline at the 3-month evaluation point (from 984 ± 22 ms to 1042 ± 28 ms, p < 0.01), predating LVEF drops by an average of 6 months. ECV fractions rose concurrently from 25.4% ± 1.8% to 29.2% ± 2.1% (p < 0.05). Multivariable Cox regression confirmed that a 3-month native T1 increase greater than 50 ms was an independent predictor of subsequent clinical cardiotoxicity (hazard ratio: 2.65, 95% CI: 1.45–4.84, p = 0.002). Cardiovascular magnetic resonance native T1 mapping serves as a highly sensitive tool for the early detection of diffuse subclinical myocardial changes induced by anthracyclines, offering an earlier window for cardioprotective intervention than traditional ejection fraction tracking.

Keywords: Cardio-oncology, Anthracyclines, Cardiotoxicity, Cardiac magnetic resonance, T1 mapping, Extracellular volume

Received: January 10, 2019; Revised: February 22, 2019; Accepted: March 15, 2019; Published: April 18, 2019

International Journal of Cardiology | Vol. 9, No. 12, December 2018 | pp. 89–96

DOI: 10.46882/2018/IJC/000117

Original Research Article

Volumetric Quantification of Epicardial Adipose Tissue via MDCT and Its Prognostic Impact on Stable CAD

Yusuf Demir¹, Murat Kaya¹, Ahmet Yilmaz²

¹Department of Cardiology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey

²Division of Cardiovascular Radiology, Hacettepe University Faculty of Medicine, Ankara, Turkey

Abstract:
Epicardial adipose tissue (EAT) is a metabolically active visceral fat depot surrounding the myocardium that secretes various pro-inflammatory adipokines. While excessive EAT is associated with general metabolic syndromes, its independent prognostic impact on ischemic event recurrence in patients with established coronary artery disease (CAD) remains quantified. This prospective study evaluated the prevalence of increased EAT volume measured via multidetector computed tomography (MDCT) and determined its correlation with long-term cardiovascular events. We enrolled 240 patients with angiographically documented stable CAD who underwent chest MDCT scans. EAT volume was quantified off-line using volumetric tracking software. Hyper-EAT was defined as an EAT volume greater than 125 cm³. Patients were followed over a 3-year period for major adverse cardiac events (MACE), which included cardiac death, non-fatal myocardial infarction, or unstable angina requiring hospitalization. An elevated EAT volume was identified in 92 patients (38.3%). During follow-up, MACE occurred in 38 patients (15.8%). The incidence of MACE was significantly higher in the high-EAT cohort compared to the normal-EAT group (26.1% vs. 9.5%, p = 0.001). Multivariable Cox proportional hazards analysis confirmed that an increased EAT volume was an independent predictor of recurrent MACE (hazard ratio: 2.15, 95% CI: 1.28–3.62, p = 0.003) after adjusting for age, body mass index, lipid profiles, and the baseline coronary artery calcium score. Subclinical accumulation of epicardial adipose tissue is prevalent in patients with stable coronary artery disease and serves as a powerful, independent predictor of long-term ischemic events, reflecting the clinical importance of local visceral adiposity in atheroprogression.

Keywords: Epicardial adipose tissue, Coronary artery disease, Visceral fat, Computed tomography, Inflammation, Prognosis

Received: September 15, 2013; Revised: October 28, 2013; Accepted: November 15, 2013; Published: December 19, 2018

International Journal of Cardiology | Vol. 9, No. 4, April 2018 | pp. 25–32

DOI: 10.46882/2018/IJC/000109

Original Research Article

Prevalence and Prognostic Significance of Subclinical Left Ventricular Dysfunction in Asymptomatic Severe Primary Mitral Regurgitation

Elena R. Petrova¹, Dmitry V. Ivanov¹, Sergei N. Kozlov²

¹Department of Cardiology, Almazov National Medical Research Centre, St. Petersburg, Russia

²Division of Cardiovascular Surgery, Research Institute of Circulation Pathology, Novosibirsk, Russia

Abstract:
Timing surgical intervention in asymptomatic patients with severe primary mitral regurgitation (MR) and preserved left ventricular ejection fraction (LVEF greater than or equal to 60%) remains highly challenging. Subclinical myocardial dysfunction may develop before conventional threshold parameters are met. This study determined the prevalence of subclinical left ventricular dysfunction using global longitudinal strain (GLS) and evaluated its prognostic value for predicting post-operative heart failure development. We prospectively enrolled 115 asymptomatic patients with severe primary organic MR and an LVEF greater than or equal to 60%. Baseline standard and speckle-tracking echocardiography measured LVEF, left ventricular end-systolic diameter (LVESD), and GLS. Patients were tracked over a median of 38 months for the primary composite endpoint of heart failure symptom onset, new resting LVEF reduction less than 60%, or cardiac mortality. Subclinical LV dysfunction, defined as an absolute baseline GLS less than 18%, was identified in 38 patients (33.0%) despite a normal mean LVEF (64.2% ± 2.8%). The primary endpoint occurred in 28 patients (24.3%). Kaplan-Meier analysis revealed significantly lower event-free survival in patients with impaired GLS (log-rank p = 0.002). Multivariable Cox regression confirmed that an absolute GLS less than 18% was an independent predictor of long-term clinical worsening (hazard ratio: 2.12, 95% CI: 1.22–3.68, p = 0.005), outperforming conventional parameters like LVESD. Subclinical left ventricular dysfunction is prevalent in a third of asymptomatic patients with severe primary mitral regurgitation.

Keywords: Primary mitral regurgitation, Echocardiography, Global longitudinal strain, Subclinical dysfunction, Prognosis, Mitral valve surgery

Received: January 08, 2013; Revised: February 20, 2013; Accepted: March 12, 2013; Published: April 18, 2018

International Journal of Cardiology | Vol. 9, No. 11, November 2018 | pp. 81–88

DOI: 10.46882/2018/IJC/000116

Original Research Article

Quantitative Scar Characterization via Late Gadolinium Enhancement CMR for Predicting Myocardial Viability post-CABG

Vasily Smirnov¹, Elena Kuzmina², Dmitry Ivanov¹

¹Department of Cardiology, Almazov National Medical Research Centre, St. Petersburg, Russia

²Division of Cardiovascular Imaging, Pavlov First Saint Petersburg State Medical University, St. Petersburg, Russia

Abstract:
In patients with ischemic cardiomyopathy and severely reduced left ventricular function, selecting candidates for surgical revascularization depends on verifying viable myocardium. Late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) allows for precise quantification of transmural scar extent. This prospective study evaluated the long-term prognostic value of CMR-derived myocardial viability parameters in predicting functional recovery and survival after coronary artery bypass grafting (CABG). We followed 165 patients with chronic coronary artery disease and a baseline LVEF less than or equal to 35% who underwent viability evaluation via LGE-CMR prior to planned CABG. Myocardial segments were classified as viable if the transmural extent of scar tissue was less than or equal to 50%. A significant amount of viable myocardium was defined as greater than or equal to 4 viable segments within a 17-segment model. Patients were tracked over a median of 4.5 years for a composite primary endpoint of cardiac death or heart failure hospitalization. A significant viable myocardium profile was identified in 98 patients (59.4%). At 6 months post-CABG, 78.5% of the viable cohort demonstrated an absolute increase in LVEF greater than or equal to 5%, compared with only 12.0% of the non-viable cohort (p < 0.001). Over the full follow-up period, patients with viable myocardium experienced significantly better event-free survival than non-viable individuals (log-rank p = 0.002). Multivariable Cox regression confirmed that the absolute number of viable segments was an independent predictor of long-term survival (hazard ratio: 0.78 per segment, 95% CI: 0.66–0.92, p = 0.004). Quantitative scar characterization via late gadolinium enhancement CMR effectively predicts functional recovery and long-term event-free survival in patients with ischemic cardiomyopathy undergoing surgical revascularization.

Keywords: Ischemic cardiomyopathy, Myocardial viability, Cardiac magnetic resonance, Late gadolinium enhancement, Coronary artery bypass grafting, Prognosis

Received: August 10, 2013; Revised: September 22, 2013; Accepted: October 14, 2013; Published: November 20, 2018

International Journal of Cardiology | Vol. 9, No. 5, May 2018 | pp. 33–40

DOI: 10.46882/2018/IJC/000110

Original Research Article

Three-Year Efficacy and Safety of Catheter Ablation for Atrial Fibrillation Rhythm Control in Hypertrophic Cardiomyopathy

Alessandro Mancini¹, Roberto Romano¹, Giovanni Esposito²

¹Department of Cardiovascular Sciences, University of Naples Federico II, Naples, Italy

²Division of Electrophysiology, San Raffaele Hospital, Milan, Italy

Abstract:
Atrial fibrillation (AF) is the most frequent sustained arrhythmia in patients with hypertrophic cardiomyopathy (HCM), poorly tolerated due to diastolic dysfunction, and associated with heart failure acceleration and stroke. Catheter ablation is an effective rhythm control strategy in general cohorts, but its long-term durability in structurally remodeled HCM hearts remains unclear. This study evaluated the 3-year efficacy and safety of catheter ablation for paroxysmal or persistent AF in patients with HCM. We prospectively followed 85 consecutive HCM patients who underwent radiofrequency catheter ablation (pulmonary vein isolation with or without additional linear/substrate ablation). The primary endpoint was freedom from recurrent atrial tachyarrhythmias lasting longer than 30 seconds after a 90-day blanking period. At 3-year follow-up, overall freedom from recurrent AF was achieved in 51.8% of patients after a single procedure, increasing to 68.2% after a secondary procedure (repeat intervention required in 22.4% of patients). Success rates were significantly higher in patients with paroxysmal AF than in those with persistent AF (64.5% vs. 37.0%, p = 0.01). Left atrial diameter greater than or equal to 48 mm was identified as an independent predictor of arrhythmia recurrence (hazard ratio: 1.85, 95% CI: 1.12–3.04, p = 0.02). Periprocedural major complications included 2 cases of femoral pseudoaneurysm and 1 case of transient ischemic attack, with no procedurally related deaths. Catheter ablation is safe and moderately effective for long-term rhythm control in HCM patients, achieving higher success rates when performed early during the paroxysmal phase.

Keywords: Hypertrophic cardiomyopathy, Atrial fibrillation, Catheter ablation, Pulmonary vein isolation, Recurrence, Remodeling

Received: February 12, 2013; Revised: March 25, 2013; Accepted: April 10, 2013; Published: May 20, 2018

International Journal of Cardiology | Vol. 9, No. 9, September 2018 | pp. 65–72

DOI: 10.46882/2018/IJC/000114

Original Research Article

Two-Year Efficacy and Safety of Percutaneous Left Atrial Appendage Closure versus Direct Oral Anticoagulants

Matteo Barbieri¹, Luigi Marini², Francesca Costa¹

¹Department of Cardiology, San Raffaele Hospital, Milan, Italy

²Division of Interventional Cardiology, University Hospital of Bologna, Bologna, Italy

Abstract:
Oral anticoagulation is standard for stroke prevention in non-valvular atrial fibrillation (AF), but compliance can be limited by recurrent bleeding. Percutaneous left atrial appendage closure (LAAC) serves as a mechanical alternative. This prospective observational study evaluated the 2-year efficacy and safety of LAAC using the Watchman device compared with direct oral anticoagulants (DOACs) in patients at high risk of stroke and bleeding. We evaluated 210 patients with non-valvular AF and a HAS-BLED score greater than or equal to 3 who underwent successful LAAC (n = 105) or received standard DOAC therapy (apixaban or rivaroxaban, n = 105). The primary efficacy endpoint was a composite of ischemic stroke, systemic embolism, or cardiovascular mortality at 24 months. The primary safety endpoint was major bleeding according to BARC criteria. At 24 months, the primary efficacy endpoint did not differ significantly between the LAAC and DOAC groups (4.8% vs. 5.7%, hazard ratio: 0.82, 95% CI: 0.25–2.68, p = 0.74). However, the incidence of major bleeding was significantly lower in the LAAC group than in the DOAC cohort after the initial 3-month post-procedural period (2.9% vs. 10.5%, hazard ratio: 0.26, 95% CI: 0.08–0.88, p = 0.02). Device-related thrombus was detected in 3.8% of LAAC patients via transesophageal echocardiography, successfully managed with temporary anticoagulation. Percutaneous left atrial appendage closure provides stroke protection non-inferior to direct oral anticoagulants while significantly reducing long-term major bleeding risks in high-risk atrial fibrillation patients.

Keywords: Atrial fibrillation, Left atrial appendage closure, Direct oral anticoagulants, Ischemic stroke, Major bleeding, Watchman device

Received: June 08, 2013; Revised: July 20, 2013; Accepted: August 12, 2013; Published: September 18, 2018