Dr. Usman's Cardiology Notes

  Cardiac Resynchronization Therapy (CRT): Indications, Guidelines and Clinical Decision-Making A practical, guideline-based guide for cardiologists, electrophysiologists, postgraduate trainees and medical students. Introduction Cardiac resynchronization therapy (CRT) is a device-based treatment for selected patients with heart failure and ventricular electrical dyssynchrony. By coordinating right and left ventricular activation, CRT can improve left ventricular systolic function, reduce heart failure hospitalizations, improve functional status and, in appropriately selected patients, reduce mortality. Patient selection is critical. The greatest benefit is generally observed in patients with heart failure with reduced ejection fraction (HFrEF), left bundle branch block (LBBB), and a markedly prolonged QRS duration. Key clinical message The classic CRT candidate has LVEF ≤35%, persistent symptoms despite guideline-directed medical therapy (GDMT), sinus rhythm, LBBB mo...

2026 ESC Heart Failure Guidelines: Classification, Diagnosis and Treatment A practical clinical review for cardiologists, physicians, postgraduate trainees and medical students. Introduction The 2026 European Society of Cardiology (ESC) Guidelines for the Management of Heart Failure introduce important changes in the classification, prevention, diagnosis and treatment of heart failure (HF). Published on 28 August 2026, these guidelines update the previous ESC recommendations and emphasize early diagnosis, prevention of disease progression and individualized treatment. The major changes include a simplified classification based on left ventricular ejection fraction (LVEF), adoption of HF stages A–D, revised terminology for medical therapies and updated recommendations for pharmacological and device-based treatment. Key update: The 2026 ESC guidelines eliminate the separate HFmrEF category. HFrEF is defined by LVEF below 50%, whereas HFpEF is defined by LVEF of 50% or higher,...

  Cardiovascular Features of Connective Tissue Diseases Connective tissue disorders are a diverse group of inherited conditions that can affect the cardiovascular system, particularly the aorta, systemic arteries, cardiac valves, and myocardium. Some of these disorders are associated with a significant risk of aortic aneurysm, dissection, arterial rupture, or premature vascular disease. Recognizing the characteristic cardiovascular phenotype of each disorder is important for early diagnosis, appropriate imaging surveillance, family screening, and prevention of life-threatening complications. Marfan Syndrome Marfan syndrome is an autosomal dominant connective tissue disorder caused primarily by pathogenic variants in the FBN1 gene, which encodes fibrillin-1. The most important cardiovascular manifestation is aortic root dilatation , particularly involving the sinuses of Valsalva. Progressive aortic enlargement can result in aortic aneurysm, aortic regurgitation, and aortic dissect...

Temporary Pacemaker (TPM) Lead Settings and Troubleshooting: A Practical Guide Temporary pacemakers (TPMs) are commonly used for patients with symptomatic bradycardia, high-grade AV block, sinus node dysfunction, post-cardiac surgery conduction disturbances, acute myocardial infarction, drug-induced bradyarrhythmias, and during electrophysiology procedures. Safe temporary pacing requires an understanding of the pacing rate, output, sensitivity, capture threshold, sensing threshold, pacing mode, and lead integrity. This article provides a practical approach to temporary pacemaker lead settings, threshold testing, and troubleshooting. 1. Basic Components of a Temporary Pacemaker System A temporary pacing system consists of: Temporary pacing lead External pulse generator Connecting cable Battery/power source ECG and haemodynamic monitoring The pacing lead has two major functions: Pacing: delivering an electrical stimulus to the myocardium. Sensing: detecting intrin...

  2026 AHA/ACC Guideline for Preoperative Cardiovascular Risk Assessment Before Noncardiac Surgery The 2026 AHA/ACC Guideline for Perioperative Cardiovascular Management of Patients Undergoing Noncardiac Surgery provides a structured, stepwise approach to evaluating cardiovascular risk before surgery. Importantly, the 2026 guideline is a reaffirmation of the 2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM guideline. After reviewing evidence published during the preceding two years, the ACC/AHA Joint Committee concluded in September 2026 that the 2024 recommendations remain valid and current. The recommendations and supporting material are unchanged. The central principle is simple: preoperative cardiovascular assessment should identify patients who may benefit from optimization or additional testing without unnecessarily delaying surgery or exposing patients to low-value investigations. 1. Goals of Preoperative Cardiovascular Assessment The purpose of preoperative cardiovascular evalua...