Search results for "QRS"
showing 7 items of 37 documents
The electrocardiographic ‘triangular QRS-ST-T waveform’ pattern : a marker of severe haemodynamic compromise in Takotsubo syndrome : a case report
2020
Abstract Background Takotsubo cardiomyopathy is characterized by transient regional systolic dysfunction of the left ventricle, mimicking myocardial infarction. Although systolic left ventricular (LV) function normalizes in most cases, the outcome is not always favourable. Recently, a rare electrocardiogram (ECG) finding, lambda wave ST elevation or ‘triangular QRS-ST-T waveform’, was suggested as a possible marker of poor outcome in Takotsubo patients Case summary After a brief episode of chest pain and shortness of breath, a 67-year-old woman developed cardiogenic shock. Her resting ECG showed widespread ST elevations, which soon evolved into a pattern of triangular QRS-ST-T waveforms in …
A particular bigeminy during atrial tachycardia.
2014
The ECG shows clearly visible P waves only in lead V1 (Fig. 1). Regular PP intervals and an isoelectric baseline are present between the P waves, so the diagnosis is atrial tachycardia [1]. During the ECG recording, lead V1 shows 12 P waves but some of these are not visible because they are concealed by the QRS complex (Fig. 2). In lead V1, the beats following the long RR intervals are conducted by the first and the seventh P wave and the premature QRS complexes are conducted by the third and the ninth P wave because the fourth and the tenth P wave are too close to the following QRS complex to conduct the impulse. Consequently, the atrial tachycardia presents an alternating 2:1 and 4:1 cond…
Genetic analyses of the QT interval and its components in over 250K individuals identifies new loci and pathways affecting ventricular depolarization…
2021
AbstractThe QT interval is an electrocardiographic measure representing the sum of ventricular depolarization (QRS duration) and repolarization (JT interval). Abnormalities of the QT interval are associated with potentially fatal ventricular arrhythmia. We conducted genome-wide multi-ancestry analyses in >250,000 individuals and identified 177, 156 and 121 independent loci for QT, JT and QRS, respectively, including a male-specific X-chromosome locus. Using gene-based rare-variant methods, we identified associations with Mendelian disease genes. Enrichments were observed in established pathways for QT and JT, with new genes indicated in insulin-receptor signalling and cardiac energy meta…
Survival with Cardiac-Resynchronization Therapy in Mild Heart Failure
2014
BACKGROUND The Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy (MADIT-CRT) showed that early intervention with cardiac-resynchronization therapy with a defibrillator (CRT-D) in patients with an electrocardiographic pattern showing left bundle-branch block was associated with a significant reduction in heart-failure events over a median follow-up of 2.4 years, as compared with defibrillator therapy alone. METHODS We evaluated the effect of CRT-D on long-term survival in the MADIT-CRT population. Post-trial follow-up over a median period of 5.6 years was assessed among all 1691 surviving patients (phase 1) and subsequently among 854 patients who w…
Non-responders to cardiac resynchronization therapy: Insights from multimodality imaging and electrocardiography. A brief review
2016
Background Cardiac resynchronization therapy (CRT) is a successful strategy for heart failure (HF) patients. The pre-requisite for the response is the evidence of electrical dyssynchrony on the surface electrocardiogram usually as left bundle branch block (LBBB). Non-response to CRT is a significant problem in clinical practice. Patient selection, inadequate delivery and sub-optimal left ventricle lead position may be important causes. Objectives In an effort to improve CRT response multimodality imaging (especially echocardiography, computed tomography and cardiac magnetic resonance) could play a decisive role and extensive literature has been published on the matter. However, we are so fa…
The QRS narrowing index for easy and early identification of responder to cardiac resynchronization therapy.
2013
The rationale for cardiac resynchronization therapy (CRT) in patients with heart failure (HF) is based on the possibility of inducing substantial left ventricular reverse remodeling. It is well known that some of these patients don't benefit from this therapy (the so-called non-responders) [1,2]. No better predictors of a positive answer to CRT than pre-CRT QRS duration (QRSd) were found [3,4]. The aim of our study was to identify a parameter for an easy and early identification of responders to CRT. In this regard, according to Rickard et al., we identified and observed QRS index (QI), as an expression of electrical remodeling after CRT, and its relation with anatomic reverse remodeling, e…
Decompressive Craniectomy Improves QTc Interval in Traumatic Brain Injury Patients
2020
Background: Traumatic brain injury (TBI) is commonly associated with cardiac dysfunction, which may be reflected by abnormal electrocardiograms (ECG) and/or contractility. TBI-related cardiac disorders depend on the type of cerebral injury, the region of brain damage and the severity of the intracranial hypertension. Decompressive craniectomy (DC) is commonly used to reduce intra-cranial hypertension (ICH). Although DC decreases ICH rapidly, its effect on ECG has not been systematically studied. The aim of this study was to analyze the changes in ECG in patients undergoing DC. Methods: Adult patients without previously known cardiac diseases treated for isolated TBI with DC were studied. EC…