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Cardiovascular changes with aging
Published in Wilbert S. Aronow, Jerome L. Fleg, Michael W. Rich, Tresch and Aronow’s Cardiovascular Disease in the Elderly, 2019
The cardiac conduction system undergoes multiple changes with age that affect its electrical properties and, when exaggerated, cause clinical disease. A generalized increase in elastic and collagenous tissue commonly occurs. Fat accumulates around the sinoatrial node, sometimes creating partial or complete separation of the node from the atrial tissue. In extreme cases, this may contribute to the development of sick sinus syndrome. A pronounced decline in the number of pacemaker cells generally occurs after age 60; by age 75, less than 10% of the number seen in young adults remain. A variable degree of calcification of the left side of the cardiac skeleton, which includes the aortic and mitral annuli, the central fibrous body, and the summit of the interventricular system, is observed. Because of their proximity to these structures, the atrioventricular (AV) node, AV bifurcation, and proximal left and right bundle branches may be damaged or destroyed by this process, resulting in AV or intraventricular block.
Stimulants, antidepressants, antimanics, anticonvulsants, and psychotomimetic agents
Published in Bev-Lorraine True, Robert H. Dreisbach, Dreisbach’s HANDBOOK of POISONING, 2001
Bev-Lorraine True, Robert H. Dreisbach
The ECG may reveal atrioventricular or intraventricular block, prolonged PR and QT intervals, widened QRS complex, flat or inverted Τ waves, supraventricular or ventricular tachycardia, ventricular fibrillation or asystole.
Management of Wolff-Parkinson-White syndrome in a patient with peripartum cardiomyopathy
Published in Journal of Community Hospital Internal Medicine Perspectives, 2021
Snigdha Bendaram, Sherif Elkattawy, Muhammad Atif Masood Noori, Hardik Fichadiya, Sarah Ayad, Parminder Kaur, Raja Pullatt, Fayez Shamoon
In ED, the patient was found to have a BP of 76/50. EKG (EKG a) showed Narrow complex tachycardia with a nonspecific intraventricular block and a heart rate of 190 beats per minutelikely mechanism being orthodromic AVRT given presence of delta wave in prior resting EKG. Also, a QTc of 533 milliseconds was noted. Serum magnesium was 1.6 mg/dl, which was repleted. She was treated with two doses of 100 mg intravenous procainamide, which reverted the cardiac rhythm to sinus rhythm and raised the patients blood pressure to 110/70 mmHg. A white blood cell count of 12,4004/mm3 (Normal range 4,000–10,000) was noted. Brain natriuretic peptide levels were 916 pg/ml (Normal <100). Chest X-ray showed findings suggestive of a small left pleural effusion; CT angiography was negative for Pulmonary embolism but did show findings concerning left lower lobe bronchopneumonia with trace pericardial and bilateral pleural effusions. The patient was given ceftriaxone and doxycycline, was continued on procainamide infusion and admitted to the Intensive care unit for further management.
Cardioprotective effects of hesperidin on carbon monoxide poisoned in rats
Published in Drug and Chemical Toxicology, 2021
Ramin Rezaee, Alireza Sheidary, Saeedeh Jangjoo, Sarvenaz Ekhtiary, Somayeh Bagheri, Zahra Kohkan, Madjid Dadres, Anca Oana Docea, Konstantinos Tsarouhas, Dimosthenis A. Sarigiannis, Spyros Karakitsios, Aristidis Tsatsakis, Leda Kovatsi, Mahmoud Hashemzaei
Ischemia and myocardial injury are common in moderate to severe CO intoxication (Kaya et al. 2016). Data from human studies showed ischemic electrocardiogram (ECG) changes following CO poisoning, including T wave flattening or inversion, ST segment elevation and depression, QT prolongation, atrial fibrillation and intraventricular block (Weaver 2009). The most commonly reported ECG changes are T wave abnormality and S–T segment changes (elevation and depression) (Weaver 2009). Moreover, ventricular tachycardia and fibrillation were demonstrated following severe CO poisoning in rats (Weaver 2009).
The effects of atorvastatin and rosuvastatin on exercise tolerance in patients with coronary heart disease
Published in Expert Opinion on Drug Safety, 2020
Dan Liu, Tao Shen, Chuan Ren, Shunlin Xu, Lequn Zhou, Jin Bai, Nan Li, Wei Zhao, Wei Gao
The ULTIMACardio2 gas exchange analysis system (Medgraphics Corp, USA) was used in our study. Bruce protocol stress test was adopted for treadmill exercise test with each stage lasting 3 minutes. Ramp protocol was used in the cycling test, which was, patients rested on the exercise bike for 3 min, cycled for another 3 min without load and continued to cycle with increased load until peak exercise capacity or exercise cessation. Participants should maintain a uniform speed of 60–70 r/min when cycling. Electrocardiogram, blood pressure and whole-body response were monitored during exercise test. Besides, patients were encouraged to perform symptom-restricted exercise (fatigue self-assessment scale scored 16–20; and respiratory exchange rate ≥1.1). Exercise would be terminated if any of the following conditions had occurred: typical angina; obvious signs and symptoms including difficulty in breathing, pale face, cyanosis, dizziness, vertigo, gait instability, movement disorders, ischemic claudication; increased lower extremity discomfort or pain with increased exercise intensity; horizontal or down-sloping ST-segment depression≥0.15 mV or injured ST-segment elevation≥2.0 mV; malignant arrhythmia, such as ventricular tachycardia, ventricular fibrillation, R-on-T premature beats, supraventricular tachycardia, multi-source frequent ventricular premature beats, atrial fibrillation, etc.; no systolic blood pressure increase or the decrease in systolic blood pressure>10 mmHg during exercise; systolic blood pressure over 220 mmHg; intraventricular block caused by exercise; exercise cessation required by participants. All participants were observed for 5 min under no load after test. The whole process was carried out with ECG monitoring by physicians, and information such as ECG, blood pressure and gas metabolism was continuously collected and recorded. All test results were analyzed and adopted as valid test data. At the same time, the continuous parameters of CPET, such as heart rate, blood pressure, gas metabolism and electrocardiogram were adopted in the analysis. The major parameters in this study included VO2peak (ml/kg/min), oxygen uptake at anaerobic threshold (VO2AT, ml/kg/min), oxygen pulse at peak oxygen uptake (VO2/HR@VO2peak, ml/beat), ventilation per carbon dioxide output slope (VE/VCO2 slope), and oxygen uptake efficiency slope (OUES).