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Assessment of LV Diastolic Function by Echo in SR and AF
Echocardiographic assessment of left ventricular diastolic function with special reference on diastolic function assessment in atrial fibrillation. Though there are several parameters for evaluation of left ventricular diastolic function by echocardiography, the most commonly used are the pulsed Doppler mitral E/A ratio and tissue Doppler mitral E/e’ ratio. Some of the other useful parameters are mitral E velocity deceleration time, changes in mitral inflow with Valsalva maneuver, mitral L velocity, isovolumic relaxation time, left atrial maximum volume index, pulmonary vein systolic/diastolic velocity ratio, color M-mod...
Source: Cardiophile MD - April 15, 2024 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs

Ventricular Fibrillation, ICD, LBBB, QRS of 210 ms, Positive Smith Modified Sgarbossa Criteria, and Pacemaker-Mediated Tachycardia
An elderly man collapsed. There was no bystander CPR. Medics found him in ventricular fibrillation. He was defibrillated, but they also noticed that he was being internally defibrillated and then found that he had an implantable ICD.He was unidentified and there were no records availableAfter 7 shocks, he was successfully defibrillated and brought to the ED.Bedside ED ultrasound showed exceedingly poor global LV function, and no B lines.Here is the initial ED ECG. What do you think?Rhythm: Residents asked me why it is not VT. If you use calipers (or equvalent), it is clear that the rhythm...
Source: Dr. Smith's ECG Blog - April 2, 2024 Category: Cardiology Authors: Steve Smith Source Type: blogs

Why ICDs are less effective in Non Ischemic DCM ?
We wish, our understanding about cardiac contractile physiology is deep and nearly complete. Heart is an irreversibly coupled electro-mechanical organ , right from the fetal days until the final heart beat. In myocardial pathology, the genesis and sustainability of ventricular arrhythmia are intricately related to the degree of LV dysfunction of any cause. SCD is the leading cause of mortality in heart failure. Tackling SCD was in God’s domain, until the brilliance of Dr. Michel Mirowski shrunk the defibrillator and implanted it under the chest in 1980. (Dr. MM’s s a unique and inspiring story, from Poland a...
Source: Dr.S.Venkatesan MD - February 20, 2024 Category: Cardiology Authors: dr s venkatesan Tags: Uncategorized crt device crt-p vs crt-d danish trial ischemic dcm madit trial non ischemic dcm Source Type: blogs

What kind of AV block is this? And why does she develop Ventricular Tachycardia?
Discussion: The initial ECG in today ' s case is pathological for any patient, especially for a 50-year old previously heathy female. Extensive conduction system abnormalities can have various causes (ischemia, genetic, infectious, amyloid, etc). Usually the medical history will provide clues to the cause. Even though the primary suspicion was not ischemic heart disease, a CT angiogram was performed, and it revealed normal coronary arteries. This ruled out coronary disease as the cause of conduction system disease. When assessing patients with early onset high grade conduction disorders and ventricular tachydysrhythmi...
Source: Dr. Smith's ECG Blog - January 23, 2024 Category: Cardiology Authors: Magnus Nossen Source Type: blogs

COAPT Trial of Transcatheter Mitral Valve Repair in Patients with Heart Failure
Patients with heart failure and left ventricular dilatation may have secondary or functional mitral regurgitation. This is due to alteration of the left ventricular geometry producing changes in the functioning of papillary muscles and chordae tendineae and poor coaptation of the mitral leaflets. Secondary mitral regurgitation causes volume overloading of the left ventricle and is associated with reduced survival, increased hospitalization rates and decreased quality of life [1, 2]. Secondary mitral regurgitation can be reduced by guideline directed medical therapy and cardiac resynchronization therapy. This will also pro...
Source: Cardiophile MD - June 5, 2023 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Structural Heart Disease Interventions Source Type: blogs

Heart failure in chronic kidney disease – Cardiology Basics
Heart failure in chronic kidney disease – Cardiology Basics Prevalence of both heart failure and chronic kidney disease (CKD) are increasing as the population is aging globally. Hence heart failure in chronic kidney disease is seen more often. Presence of CKD in heart failure increases morbidity and mortality. Though there is increasing use of effective medications and special devices like cardiac resynchronization therapy in heart failure patients in general, those with CKD have not been benefited well. CKD is defined as abnormalities of kidney structure or function, present for >3 months, with implications for h...
Source: Cardiophile MD - October 21, 2022 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs

What is complete heart block? Cardiology Basics
When natural pacemaker impulses from the sinoatrial node fails to reach the ventricles and activate them, it is known as complete heart block. The block could be at the level of the atrioventricular (AV) node or below that. Sinus node is a subepicardial structure located in the upper part of right atrium near the orifice of the superior vena cava. Signals from sinus node travel to the AV node through three internodal pathways. They are Wenckebach, Thorel and Bachmann bundles. Bachmann bundle gives a branch to the left atrium also. AV node is located near the atrioventricular junction in the lower part of right atrium. It ...
Source: Cardiophile MD - October 17, 2022 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs

What is the difference between CRT-P and CRT-D? Cardiology Basics
In cardiology, CRT stands for cardiac resynchronization therapy. CRT is used in heart failure with reduced ejection fraction. According to the Universal Definition and Classification of Heart Failure, heart failure with reduced ejection fraction has left ventricular ejection fraction of 40% or less. CRT is a type of pacemaker in which three chambers of the heart are paced, right atrium, right ventricle and left ventricle. This picture illustrates what reduced ejection fraction means. Ejection fraction is the fraction of end diastolic volume which is pumped out from the left ventricle during systole. Normal ejection fracti...
Source: Cardiophile MD - October 13, 2022 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs

Single chamber or dual chamber pacemaker? Cardiology Basics
The decision between single chamber and dual chamber pacemaker though important based on cost, device longevity and complication wise, is not that easy to make. I am trying to summarize based on the 2018 American College of Cardiology/American Heart Association/Heart Rhythm Society guidelines on this aspect [1]. In underprivileged regions, given an option, there is always a potential bias towards single chamber devices as they are cheaper, tend to have more battery life, easier to implant and likely to have lesser procedure and lead related issues. In symptomatic sinus node dysfunction, with correlation between symptoms a...
Source: Cardiophile MD - October 10, 2022 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs

Left bundle branch-optimized cardiac resynchronization therapy (LOT-CRT)
Cardiac resynchronization therapy (CRT) is usually done by biventricular pacing with a right ventricular lead and a left ventricular lead in a coronary vein. This often results in relatively broader QRS complex and suboptimal response. A new approach is to use left bundle branch area pacing in lieu of the usual right ventricular lead and coronary venous left ventricular pacing. This novel approach has been called left bundle branch–optimized cardiac resynchronization therapy (LOT-CRT) [1]. International LBBAP collaborative study group assessed the feasibility of LBBAP-optimized CRT in non consecutive patients with ...
Source: Cardiophile MD - October 2, 2022 Category: Cardiology Authors: Johnson Francis Tags: ECG / Electrophysiology Source Type: blogs

Coronary venous circulation
Importance of knowing the coronary venous circulation has increased in recent years with use of cardiac resynchronization therapy (CRT) for heart failure. Left ventricular epicardial pacing in CRT is achieved by placing a lead in a coronary vein, usually a posterolateral tributary of the coronary sinus. Coronary venous circulation can be visualized by a coronary angiogram levophase. After filling the coronary arteries, the contrast drains into the coronary venous system, finally opacifying the coronary sinus, which drains into the right atrium. Here is a coronary angiogram levophase, with a line diagram beside it: Coronar...
Source: Cardiophile MD - June 26, 2021 Category: Cardiology Authors: Prof. Dr. Johnson Francis Tags: Cardiology Source Type: blogs

Clinical importance of LBBB
Left bundle branch block (LBBB) is usually associated with structural heart disease, unlike right bundle branch block which may be seen without associated heart disease. LBBB is one cause for paradoxical splitting of second heart sound. Normal split closes in expiration. In paradoxical splitting, split is audible in expiration and closes in inspiration. In normal conduction sequence, left bundle branch is activated first. Hence a left bundle branch block can affect the initial vector in the ECG. This leads to errors in interpretation of Q waves in myocardial infarction. Secondary ST segment and T wave abnormalities common...
Source: Cardiophile MD - June 17, 2021 Category: Cardiology Authors: Prof. Dr. Johnson Francis Tags: ECG / Electrophysiology Source Type: blogs

Left ventricular reverse remodeling
In this study, change in LVESV was the single most important predictor of all cause and cardiovascular mortality. Clinical parameters could not predict outcome events in this study. Similar beneficial effect on left ventricular remodeling was demonstrated long back in the trials with angiotensin converting enzyme inhibitors. SOLVD (Studies of Left Ventricular Dysfunction) study showed that in patients with heart failure and reduced left ventricular ejection fraction, chronic treatment with angiotensin converting enzyme inhibitor enalapril prevented progressive left ventricular dilatation, systolic dysfunction and increase ...
Source: Cardiophile MD - June 11, 2021 Category: Cardiology Authors: Prof. Dr. Johnson Francis Tags: Cardiology Source Type: blogs

Left ventricular remodeling
Left ventricular remodeling occurs in response to left ventricular stress and injury. It is progressive and occurs after large myocardial infarctions and dilated cardiomyopathy. Left ventricular volume increases and the normal elliptical shape becomes globular. Left ventricular remodeling is associated with changes at microscopic level which include myocyte hypertrophy, apoptosis and increased interstitial collagen deposition [1]. Left ventricular remodeling is a central pathophysiological mechanism in advancing heart failure. Reversal of remodeling with treatment is an important goal in the management of heart failure. ...
Source: Cardiophile MD - April 2, 2021 Category: Cardiology Authors: Prof. Dr. Johnson Francis Tags: Cardiology Source Type: blogs

Estimation of PCWP from E/E ’ on Tissue Doppler Imaging
Estimation of PCWP from E/E’ on Tissue Doppler Imaging Conventionally, pulmonary capillary wedge pressure (PCWP) is measured using a catheter in the pulmonary artery. Pulmonary artery diastolic pressure measured by a Swan Ganz balloon floatation catheter at bedside is often taken as the surrogate of PCWP. Ideal method of bedside measurement is balloon occlusion of a pulmonary artery branch to get the distal pressure. But it cannot be done on a continuous basis as it will compromise flow to the territory and vascular complications can ensue. True PCWP, as the name implies, is obtained after wedging an end hole cathet...
Source: Cardiophile MD - February 27, 2021 Category: Cardiology Authors: Prof. Dr. Johnson Francis Tags: Echocardiography Estimation of PCWP from E/E' Nagueh formula Source Type: blogs