Cardiology Journal 

About: Cardiology Journal is an academic journal published by Via Medica. The journal publishes majorly in the area(s): Medicine & Myocardial infarction. It has an ISSN identifier of 1898-018X. It is also open access. Over the lifetime, 1981 publications have been published receiving 19091 citations.

Electrolyte disorders and arrhythmogenesis

Abstract: Electrolyte disorders can alter cardiac ionic currents kinetics and depending on the changes can promote proarrhythmic or antiarrhythmic effects. The present report reviews the mechanisms, electrophysiolgical (EP), electrocardiographic (ECG), and clinical consequences of electrolyte disorders. Potassium (K⁺) is the most abundent intracellular cation and hypokalemia is the most commont electrolyte abnormality encountered in clinical practice. The most significant ECG manifestation of hypokalemia is a prominent U wave. Several cardiac and non cardiac drugs are known to suppress the HERG K⁺ channel and hence the I(K), and especially in the presence of hypokalemia, can result in prolonged action potential duration and QT interval, QTU alternans, early afterdepolarizations, and torsade de pointes ventricular tachyarrythmia (TdP VT). Hyperkalemia affects up to 8% of hospitalized patients mainly in the setting of compromised renal function. The ECG manifestation of hyperkalemia depends on serum K⁺ level. At 5.5-7.0 mmol/L K⁺, tall peaked, narrow-based T waves are seen. At > 10.0 mmol/L K⁺, sinus arrest, marked intraventricular conduction delay, ventricular techycardia, and ventricular fibrillation can develop. Isolated abnormalities of extracellular calcium (Ca⁺⁺) produce clinically significant EP effects only when they are extreme in either direction. Hypocalcemia, frequently seen in the setting of chronic renal insufficiency, results in prolonged ST segment and QT interval while hypercalcemia, usually seen with hyperparathyroidism, results in shortening of both intervals. Although magnesium is the second most abudent intracellular cation, the significance of magnesium disorders are controversial partly because of the frequent association of other electrolyte abnormalities. However, IV magnesium by blocking the L-type Ca(⁺⁺) current can successfully terminate TdP VT without affecting the prolonged QT interval. Finally, despite the frequency of sodium abnormalities, particularly hyponatremia, its EP effects are rarely clinically significant.

5-fluorouracil induced cardiotoxicity: review of the literature.

Abstract: 5-fluorouracil (5-FU) is a key chemotherapeutic agent in the treatment of many gastrointestinal tract adenocarcinomas. Despite its proven therapeutic efficacy, 5-FU also possesses several undesired cardiac toxicities, including coronary vasospasm, coronary thrombosis, cardiomyopathy, and sudden cardiac death. This review addresses the incidence, mechanisms of action, clinical presentation, risk stratification, and management of 5-FU associated cardiotoxicity; it also highlights the importance of careful pre-administration cardiac risk stratification and close monitoring during and after drug administration.

Coarctation of the aorta: from fetal life to adulthood.

Abstract: Coarctation of the aorta was once viewed as a simple discrete narrowing of the aortic isthmus that could be 'cured' by surgical intervention. It is now clear that this condition may: (1) affect the aortic arch in a highly variable manner; (2) be associated with a host of other left sided heart lesions; (3) represent a wider vasculopathy within the pre-coarctation arterial tree, leading to significant prevalence of hypertension by adolescence, and subsequent risk of early morbidity and death. This review outlines the evaluation and treatment of this disease from pre-natal to adult life.

Drug induced QT prolongation

Abstract: The drug-induced QT prolongation predisposes to development of torsades de pointes (TdP) ventricular tachycardia and sudden death. The association between specific drug and development of TdP is difficult to document, therefore, QT prolongation is considered as a surrogate marker of the proarrhythmia risk. Most of the drugs prolong QT interval usually by blocking the potassium IKr current or altering trafficking of proteins forming the channel. Improved understanding of ion channel structure and kinetics and its role in repolarization has tremendous impact on understanding of the mechanisms of drug-induced QT prolongation and TdP. Proarrhythmia caused by a QT-prolonging drug occurs infrequently, and usually multiple factors need to operate to precipitate such an event including a combination of two or more drugs affecting the same pathway, hypokalemia, and possibly genetic predisposition. ECG provides unique opportunity to ensure safety of administered therapy. QT measurement is the most routine approach to a drug safety monitoring, however, there are many challenges related to methodology of measurements, accuracy of measurements, or optimal heart rate correction. Since drugs affecting repolarization not only prolong QT but also they alter T wave morphology, novel computerized methods quantifying these changes are being developed to assist physicians and drug manufacturers in monitoring safety of the drugs. The response of a patient to a drug is very individual and therefore an individualized system of drug administration and monitoring needs to be developed, which takes into account baseline QTc duration and its changes after a drug was introduced. (Cardiol J 2007; 14: 523-533).

RADIal versus femoral approach for percutaneous coronary interventions in patients with Acute Myocardial Infarction (RADIAMI): A prospective, randomized, single-center clinical trial

Abstract: Background: The transradial approach for percutaneous coronary intervention (PCI) seems to be superior to transfemoral. The safety and efficacy of transradial approach for PCI in acute myocardial infarction is not well-established. Methods: Hundred patients with acute myocardial infarction qualified to PCI were randomly assigned to transradial (group I; n = 50) and transfemoral (group II; n = 50) approaches. Results: PCI was successful for almost all patients, except one from group II. There were no significant differences between groups in X-ray exposition, volume of contrast and total procedure duration. Small but significant elongation of door to stent time in group I was caused mostly by a longer time between beginning of procedure and arterial sheath introduction. Major bleeding complications occurred in three patients from group I and seven from group II. There were no significant differences observed between the two groups. Time to ambulation in group I was significantly shorter then in group II (22.6 ± 10.3 h vs. 34.7 ± 34.6 h; p = 0.003). Conclusions: The transradial approach for PCI in acute myocardial infarction has the same efficacy as transfemoral. There are no differences in total procedure duration, X-ray exposition or volume of contrast between the two approaches. A longer time from the patient’s admission to the individual stages of the PCI procedure in group I was mostly due to the longer times of the initial stages of the procedure. The use of transradial approach reduces the time to ambulation and allows rehabilitation to begin sooner. In both groups, bleeding complications occurred rarely. (Cardiol J 2009; 16, 4: 332–340)