International Journal of Cardiology

International Journal of Cardiology | Vol. 2, No. 6, June 2011 | pp. 41–48

DOI: 10.46882/2011/IJC/000027

Original Research Article

Cardioprotective Effects of Remote Ischemic Preconditioning in Patients Undergoing Off-Pump Coronary Artery Bypass Grafting

Vasily Smirnov¹, Dmitry Ivanov¹, Elena Kuzmina²

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

²Institute of Cardiovascular Diseases, Pavlov First Saint Petersburg State Medical University, St. Petersburg, Russia

Abstract:
Myocardial injury during coronary artery bypass grafting (CABG) affects long-term surgical success. Remote ischemic preconditioning (RIPC)—induced by transient cycles of ischemia and reperfusion in a limb—represents a simple, non-invasive method to protect the myocardium. This randomized sham-controlled trial evaluated the cardioprotective efficacy of RIPC in patients undergoing off-pump CABG. We randomized 160 patients scheduled for elective off-pump CABG to either the RIPC group (n = 80) or the sham control group (n = 80). RIPC was performed immediately after anesthesia induction by inflating a standard blood pressure cuff on the upper arm to 200 mmHg for 5 minutes, followed by 5 minutes of reperfusion, for a total of 3 cycles. Myocardial injury was assessed by measuring serum cardiac troponin I (cTnI) and creatine kinase-MB (CK-MB) levels at baseline, and 6, 12, 24, and 48 hours postoperatively. The total postoperative release of cTnI, assessed by the area under the curve (AUC) over 48 hours, was reduced by 26% in the RIPC group compared to the sham group (mean AUC: 42.4 ± 11.5 ng/mL/h vs. 57.3 ± 14.2 ng/mL/h, p < 0.01). Postoperative CK-MB levels were also significantly lower in the RIPC cohort at 12 and 24 hours (p < 0.05). There were no protocol-related vascular or neurological complications in the upper extremity. Remote ischemic preconditioning significantly attenuates perioperative myocardial injury in patients undergoing off-pump coronary artery bypass surgery, demonstrating safe, easily applicable cardioprotection.

Keywords: Remote ischemic preconditioning, Myocardial injury, Coronary artery bypass grafting, Off-pump surgery, Cardiac troponin I

Received: March 15, 2011; Revised: April 22, 2011; Accepted: May 10, 2011; Published: June 18, 2011

Citation: International Journal of Cardiology, 2011, Vol. 2, No. 6, pp. 41–48, DOI: 10.46882/2011/IJC/000027

International Journal of Cardiology | Vol. 2, No. 7, July 2011 | pp. 49–56

DOI: 10.46882/2011/IJC/000028

Original Researc

International Journal of Cardiology | Vol. 2, No. 7, July 2011 | pp. 49–56

DOI: 10.46882/2011/IJC/000028

Original Research Article

Diagnostic Utility of High-Sensitivity Cardiac Troponin T for Early Rule-Out of Myocardial Infarction in the Emergency Department

Chloe Bennett¹, Thomas Wright¹, Oliver Harrison²

¹Emergency Department, St Vincent's Hospital, Sydney, New South Wales, Australia

²School of Medicine, University of Queensland, Brisbane, Queensland, Australia

Abstract:
Rapid identification or exclusion of acute myocardial infarction (AMI) in patients presenting with chest pain is vital for emergency department (ED) throughput. High-sensitivity cardiac troponin T (hs-cTnT) assays allow for lower detection limits but may compromise specificity. This study sought to evaluate the diagnostic utility of a 0-hour/2-hour accelerated diagnostic protocol utilizing hs-cTnT for rapid AMI rule-out. We prospectively evaluated 412 consecutive patients presenting to the ED with acute chest pain suggestive of acute coronary syndrome. Blood samples for hs-cTnT were drawn at presentation (0h) and 2 hours later. The final diagnosis of AMI was adjudicated by an independent committee using the universal definition. AMI was diagnosed in 58 patients (14.1%). A baseline hs-cTnT level below the limit of blank (less than 5 ng/L) coupled with an absolute change of less than 3 ng/L within 2 hours successfully ruled out AMI in 238 patients (57.8%). This 0h/2h protocol yielded a diagnostic sensitivity of 98.3% (95% CI: 90.8%–99.9%) and an exceptional negative predictive value (NPV) of 99.6% (95% CI: 97.7%–99.9%). The specificity and positive predictive value (PPV) were 66.7% and 32.6%, respectively. No patient classified as safe for early rule-out experienced an un-adjudicated myocardial infarction or cardiac death within a 30-day safety follow-up. An accelerated diagnostic protocol incorporating baseline and 2-hour hs-cTnT assays allows for rapid, exceptionally safe exclusion of acute myocardial infarction in over half of presenting ED chest pain patients.

Keywords: High-sensitivity cardiac troponin T, Acute myocardial infarction, Emergency department, Diagnosis, Chest pain, Negative predictive value

Received: April 02, 2011; Revised: May 15, 2011; Accepted: June 08, 2011; Published: July 22, 2011

Citation: International Journal of Cardiology, 2011, Vol. 2, No. 7, pp. 49–56, DOI: 10.46882/2011/IJC/000028

International Journal of Cardiology | Vol. 2, No. 5, May 2011 | pp. 33–40

DOI: 10.46882/2011/IJC/000026

Original Research Article

Safety and Efficacy of Direct Oral Anticoagulants versus Warfarin in Patients with Atrial Fibrillation and Severe Chronic Kidney Disease

Pierre Larson¹, Jean-Luc Moreau¹, Chantal Dubois²

¹Department of Cardiology, Hôpital de la Timone, Marseille, France

²Division of Nephrology, Clinique Universitaire de Bruxelles, Brussels, Belgium

Abstract:
Atrial fibrillation (AF) and chronic kidney disease (CKD) frequently coexist, multiplicatively increasing thromboembolic and major bleeding risks. Traditional vitamin K antagonists like warfarin require tedious monitoring and carry high bleeding risks in renal failure. This observational study evaluated the safety and efficacy of a direct oral anticoagulant (DOAC), apixaban, compared to warfarin in patients with AF and stage 4 CKD. We analyzed data from 195 patients with non-valvular AF and an estimated glomerular filtration rate (eGFR) between 15 and 29 mL/min/1.73m². Patients were prescribed either adjusted-dose apixaban (2.5 mg twice daily, n = 92) or warfarin (target INR 2.0–3.0, n = 103). The primary safety endpoint was major bleeding according to ISTH criteria, and the primary efficacy endpoint was a composite of stroke or systemic embolism over a 24-month follow-up. Major bleeding occurred significantly less frequently in the apixaban group than in the warfarin group (4.3% vs. 11.7%, hazard ratio: 0.36, 95% CI: 0.15–0.88, p = 0.02). The incidence of stroke or systemic embolism did not differ significantly between groups (apixaban: 2.2% vs. warfarin: 2.9%, hazard ratio: 0.74, 95% CI: 0.22–2.53, p = 0.63). Intracranial hemorrhage was completely absent in the apixaban cohort. In patients with atrial fibrillation and severe stage 4 chronic kidney disease, apixaban offers a significantly safer profile with lower major bleeding events compared to warfarin, while maintaining comparable efficacy in ischemic stroke prevention.

Keywords: Atrial fibrillation, Chronic kidney disease, Anticoagulants, Apixaban, Warfarin, Major bleeding

Received: February 20, 2011; Revised: March 24, 2011; Accepted: April 12, 2011; Published: May 20, 2011

Citation: International Journal of Cardiology, 2011, Vol. 2, No. 5, pp. 33–40, DOI: 10.46882/2011/IJC/000026

International Journal of Cardiology | Vol. 2, No. 4, April 2011 | pp. 25–32

DOI: 10.46882/2011/IJC/000025

Original Research Article

Circulating Endothelial Progenitor Cells as a Predictor of Cardiovascular Events in Patients with Coronary Artery Disease

Hiroshi Yamamoto¹, Takashi Sato¹, Kenji Nakamura²

¹Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, Osaka, Japan

²Division of Cardiology, Tokyo Medical and Dental University, Tokyo, Japan

Abstract:
Endothelial dysfunction is a fundamental process driving the progression of atherosclerosis and plaque destabilization. Circulating endothelial progenitor cells (EPCs) derived from the bone marrow play a pivotal role in continuous vascular endothelial repair. This prospective study investigated the hypothesis that reduced levels of circulating EPCs predict long-term major adverse cardiovascular events (MACE) in patients with documented coronary artery disease (CAD). We quantified CD34+/KDR+ EPCs using flow cytometry in 210 patients with stable CAD undergoing diagnostic coronary angiography. Patients were followed for a median of 4.5 years for the occurrence of MACE, which included cardiovascular death, non-fatal myocardial infarction, and unstable angina requiring urgent revascularization. Patients were stratified into tertiles based on baseline EPC counts. MACE occurred in 48 patients (22.9%) during follow-up. The cumulative event-free survival rate was significantly lower in the lowest EPC tertile compared to the highest tertile (68.6% vs. 88.6%, log-rank p < 0.001). After adjusting for conventional cardiovascular risk factors, medications, and coronary disease severity via the SYNTAX score, a low circulating EPC count remained an independent predictor of future MACE (hazard ratio for lowest vs. highest tertile: 2.34, 95% CI: 1.41–3.88, p < 0.01). No significant correlations were observed between EPC levels and procedural access complications. Reduced levels of circulating endothelial progenitor cells independently predict long-term cardiovascular events in stable CAD patients, highlighting the clinical prognostic importance of endogenous vascular repair capacity.

Keywords: Endothelial progenitor cells, Coronary artery disease, Atherosclerosis, Endothelial function, Prognosis, Flow cytometry

Received: January 15, 2011; Revised: February 28, 2011; Accepted: March 15, 2011; Published: April 25, 2011

Citation: International Journal of Cardiology, 2011, Vol. 2, No. 4, pp. 25–32, DOI: 10.46882/2011/IJC/000025

International Journal of Cardiology | Vol. 2, No. 11, November 2011 | pp. 81–88

DOI: 10.46882/2011/IJC/000032

Original Research Article

Safety and Efficacy of Second-Generation Everolimus-Eluting Stents versus First-Generation Paclitaxel-Eluting Stents in Complex Coronary Lesions

Ji-Hoon Kim¹, Min-Soo Park¹, Sung-Hoon Choi²

¹Department of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, South Korea

²Division of Interventional Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea

Abstract:
First-generation drug-eluting stents (DES) significantly reduced restenosis but raised concerns regarding late stent thrombosis, particularly in complex coronary anatomy. Second-generation DES utilize thinner struts and biocompatible polymers to enhance vascular healing. This randomized, single-blind trial evaluated the 2-year clinical outcomes of second-generation everolimus-eluting stents (EES) compared to first-generation paclitaxel-eluting stents (PES) in patients with complex coronary artery lesions. We randomized 340 patients with complex lesions (type B2 or C according to ACC/AHA criteria) to undergo PCI with either EES (n = 170) or PES (n = 170). The primary endpoint was target lesion failure (TLF) at 2 years, defined as a composite of cardiac death, target vessel myocardial infarction (MI), or ischemia-driven target lesion revascularization (TLR). At 2 years, TLF occurred in 6.5% of the EES group compared to 13.5% of the PES group (p = 0.03). This difference was primarily driven by a significant reduction in target lesion revascularization (2.9% vs. 8.2%, p < 0.05). Definite or probable stent thrombosis was significantly lower in the EES group than in the PES group (0.6% vs. 2.4%, p = 0.04). Multivariable logistic regression identified first-generation PES use as an independent predictor of 2-year TLF (odds ratio: 2.24, 95% CI: 1.12–4.48, p = 0.02). Second-generation everolimus-eluting stents demonstrate superior safety and efficacy profiles over first-generation paclitaxel-eluting stents in complex coronary lesions, characterized by lower rates of target lesion failure and stent thrombosis.

Keywords: Percutaneous coronary intervention, Drug-eluting stents, Everolimus, Paclitaxel, Complex coronary lesions, Stent thrombosis

Received: August 01, 2011; Revised: September 15, 2011; Accepted: October 10, 2011; Published: November 20, 2011

Citation: International Journal of Cardiology, 2011, Vol. 2, No. 11, pp. 81–88, DOI: 10.46882/2011/IJC/000032

International Journal of Cardiology | Vol. 2, No. 12, December 2011 | pp. 89–96

DOI: 10.46882/2011/IJC/000033

Original Research Article

International Journal of Cardiology | Vol. 2, No. 8, August 2011 | pp. 57–64

DOI: 10.46882/2011/IJC/000029

Original Research Article

Prevalence and Clinical Implications of Left Ventricular Non-Compaction in an Unselected Cohort of Cardiomyopathy Patients

Sophia Martinez¹, Carlos Gomez¹, Alejandro Rodriguez²

¹Department of Cardiology, Hospital Universitario La Paz, Madrid, Spain

²Division of Cardiovascular Imaging, Hospital Clínic de Barcelona, Barcelona, Spain

Abstract:
Left ventricular non-compaction (LVNC) is a distinct cardiomyopathy characterized by prominent ventricular trabeculations and deep intertrabecular recesses. Its true prevalence and clinical implications in general adult cardiomyopathy cohorts remain controversial due to over-diagnostic tendencies using standard echocardiography. This study investigated the prevalence and long-term prognosis of LVNC using cardiac magnetic resonance (CMR) criteria within a broad cardiomyopathy registry. We retrospectively analyzed 520 cardiomyopathy patients who underwent diagnostic CMR imaging between 2005 and 2009. LVNC was defined strictly using the Petersen criterion (non-compacted to compacted myocardium ratio greater than 2.3 in end-diastole). Clinical outcomes were tracked over a median of 4.2 years for a composite endpoint of thromboembolism, sustained ventricular arrhythmias, heart failure hospitalization, or cardiac death. Based on CMR criteria, LVNC was identified in 34 patients (6.5%), with 18 showing isolated LVNC and 16 displaying overlapping dilated cardiomyopathy features. During follow-up, the composite clinical endpoint occurred in 32.4% of LVNC patients vs. 21.4% of non-LVNC cardiomyopathy patients (p = 0.14). However, multivariable analysis revealed that the presence of LVNC itself was not an independent predictor of adverse outcomes (hazard ratio: 1.12, 95% CI: 0.65–1.94, p = 0.68). Instead, severely reduced left ventricular ejection fraction (LVEF less than 35%) and late gadolinium enhancement (LGE) presence were the only independent prognostic factors. While LVNC is present in 6.5% of cardiomyopathy patients under CMR assessment, its structural presence does not independently worsen long-term prognosis separate from underlying systolic dysfunction and myocardial scarring.

Keywords: Left ventricular non-compaction, Cardiac magnetic resonance, Cardiomyopathy, Prevalence, Prognosis, Late gadolinium enhancement

Received: May 12, 2011; Revised: June 20, 2011; Accepted: July 11, 2011; Published: August 26, 2011

Citation: International Journal of Cardiology, 2011, Vol. 2, No. 8, pp. 57–64, DOI: 10.46882/2011/IJC/000029