New q wave on ekg lead 3

BACKGROUND: To investigate the relationship between the Q wave in synthesized V7-9 leads of a baseline electrocardiogram and clinical outcomes in patients with heart failure after cardiac resynchronization therapy (CRT) device implantation. METHODS: Consecutive patients with heart failure and a left ventricular (LV) ejection fraction <35 % were retrospectively analyzed. Patients with Q waves in the synthesized V7-9 lead were defined as the qV7-9 group and those without Q waves in the synthesized V7-9 lead were defined as the non-qV7-9 group...

BACKGROUND: The standard electrocardiogram (ECG) is commonly performed in the supine posture. It may be difficult to report ECG in a supine posture for those who are unable to adopt the supine posture because of certain circumstances such as acute respiratory distress syndrome-patients who are placed in a prone position for long periods to improve oxygenation. Few data are available on the impact of the prone position on the ECG recording with electrodes on the posterior chest. Examining and analyzing the type and extent of changes observed in the prone ECG in healthy adults have become vitally valuable...

OBJECTIVE: Myocardial infarction is a leading cause of morbidity and mortality. Fibrinolytic administration is still a life-saving choice in ST-segment elevated myocardial infarction (STEMI), but the rate of successful reperfusion can be inconsistent. Failed reperfusion adds additional clinical risks to rescue percutaneous coronary intervention for STEMI patients. The interval between the peak of the T wave and the end of the T wave (Tpe) and the ratio of Tpe and a corrected measurement of the time from the start of the Q wave to the end of the T wave (Tpe/QTc ratio) are relatively new electrocardiogram (ECG) indices and have not yet been tested in STEMI patients treated with fibrinolytic agents...

ISSUE: In 2002, (before the establishment of the Ontario Health Technology Advisory Committee), the Medical Advisory Secretariat conducted a health technology policy assessment on biventricular (BiV) pacing, also called cardiac resynchronization therapy (CRT). The goal of treatment with BiV pacing is to improve cardiac output for people in heart failure (HF) with conduction defect on ECG (wide QRS interval) by synchronizing ventricular contraction. The Medical Advisory Secretariat concluded that there was evidence of short (6 months) and longer-term (12 months) effectiveness in terms of cardiac function and quality of life (QoL)...

Electrocardiographic signs of a non-ST elevation myocardial infarction (NSTEMI) are nonspecific, and therefore the diagnosis of NSTEMI during acute coronary syndromes (ACS) depends mainly on cardiac biomarker levels. Fragmented QRS (fQRS) represents myocardial conduction abnormalities due to myocardial infarction (MI) scars in patients with coronary artery disease. However, the time of appearance of fQRS during ACS has not been investigated. It was postulated that in patients with ACS, fQRS on 12-lead electrocardiography occurs within 48 hours of presentation with NSTEMI as well as ST elevation MI and that fQRS predicts mortality...

INTRODUCTION: Takotsubo syndrome (apical ballooning syndrome) was described for the first time in Japan, at the beginning of the 1990s. It is characterized by the acute onset of extensive but transient akinesia of the apical and mid portions of the left ventricle, in the absence of significant coronary disease. OBJECTIVE: We describe five patients who were admitted to our hospital with this new syndrome between June 2004 and December 2005. These patients represented 0...

QT surveillance of neonatal patients, and especially premature infants, may be important because of the potential for concomitant exposure to QT-prolonging medications and because of the possibility that they may have hereditary QT prolongation (long-QT syndrome), which is implicated in the pathogenesis of approximately 10% of sudden infant death syndrome. In-hospital automated continuous QT interval monitoring for neonatal and pediatric patients may be beneficial but is difficult because of high heart rates; inverted, biphasic, or low-amplitude T waves; noisy signal; and a limited number of electrocardiogram (ECG) leads available...

BACKGROUND: The aim of the present study was to investigate the predictive value of presentation and 24-hour electrocardiograms in defining the infarct-related artery (IRA), its lesion segment, and the right ventricular involvement in acute inferior myocardial infarction (MI). METHODS: One hundred forty-nine patients with acute inferior MI were included. Infarct-related artery, its lesion segment, and the validity of new ECG criteria for the diagnosis of right ventricular MI (RVMI) were investigated by means of criteria obtained from admission and 24- hour ECGs...

OBJECTIVES: The goal of this study was to investigate the nature of the association between silent ischemia and postoperative myocardial infarction (PMI). BACKGROUND: Silent ischemia predicts cardiac morbidity and mortality in both ambulatory and postoperative patients. Whether silent stress-induced ischemia is merely a marker of extensive coronary artery disease or has a closer association with infarction has not been determined. METHODS: In 185 consecutive patients undergoing vascular surgery, we correlated ischemia duration, as detected on a continuous 12-lead ST-trend monitoring during the period 48 h to 72 h after surgery, with cardiac troponin-I (cTn-I) measured in the first three postoperative days and with postoperative cardiac outcome...

BACKGROUND: Significant myocardial injury during cardiac surgery is associated with a 10-fold increase in 2-year complication rates, yet there remains no clinical gold standard for diagnosis. Troponin I has complete cardiospecificity and is clinically used for diagnosis of myocardial infarction in other settings. METHODS AND RESULTS: One hundred consecutive patients undergoing open heart surgery (71 coronary artery bypass grafts and 29 aortic valve replacements) were enrolled and blood samples were drawn preoperatively, at 5 AM and 5 PM on days 1 and 2 after surgery, and at 5 AM for 3 more days...

BACKGROUND: In this study, the authors intensively monitored isoenzyme and electric activity of the heart for the first 7 days after noncardiac surgery in a large group of patients at risk for postoperative myocardial infarction (PMI). METHODS: After institutional review board approval and written informed consent were received, 323 patients, aged 50 yr or older, who had ischemic heart disease and presented for noncardiac surgery, were enrolled in this prospective, blinded study...

Authors presented the basic criteria for indicating thrombolytic therapy in patients with acute myocardial infarction according to literature data and their own experience regarding the judgment of changes in initial standard electrocardiogram (without any changes after administration of nitroglycerine and/or chest pain resolution). They are: 1. ST segment elevation > or = 0.1 mV, in at least two contiguous leads, 2. new or a presumably new bundle branch block, 3. ST segment depression in thoracic leads V1-V3 in the presumptive presence of acute posterior myocardial infarction...

To determine how often acute lateral myocardial infarcts may be electrocardiographically "silent," a new approach was utilized in which subjects were selected by admission thallium scintigraphy. Thirty-one patients with their first infarction were identified with moderate to severe perfusion defects of the lateral and posterolateral walls, persistent over 7 days and associated with severe wall motion abnormalities. Patients with involvement of the anterior, septal or "inferior" regions were not included. In nine patients, the perfusion defect extended to the anterolateral wall: all developed ST elevation and Q waves in at least one of the "lateral" leads (I, aVL or V6) but none showed changes in the "inferior" leads (II, III or aVF)...

Over a 34.5-month period, all admissions to 5 university hospital coronary care units were screened for eligibility for the Multicenter Investigation of the Limitation of Infarct Size (MILIS), an ongoing study of the effects of hyaluronidase, propranolol and placebo on myocardial infarct (MI) size. Of 3,697 patients with greater than or equal to 30 minutes of discomfort that was thought to reflect myocardial ischemia who were assessed for the presence or absence of certain electrocardiographic abnormalities at the time of hospital admission, the electrocardiogram was considered predictive of acute MI if greater than or equal to 1 of the following abnormalities was present: new or presumably new Q waves (greater than or equal to 30 ms wide and 0...

The concept of high lateral myocardial infarction (HLMI) has not been clearly defined, so criteria for its vectorcardiographic (VCG) diagnosis have had no firm basis. However, we have reported that HLMI, expressed as abnormal Q waves in lead aVL on the electrocardiogram, corresponds to necrosis of the area usually supplied by the diagonal branches of the left anterior descending coronary artery. Here, we evaluated conventional VCG criteria for the diagnosis of HLMI on the basis of angiographic findings, and selected the criteria of Chou as typical...

The aim of this study was to assess the evolution of ST segment displacement and the formation of new Q waves in relation to the late angiographic demonstration of recanalization of the infarct-related vessel in 36 patients with acute myocardial infarction admitted in our Institution within 8 hours from the onset of symptoms. Eighteen patients were treated with intravenous urokinase (200,000 + 1,200,000 UI) followed by sodium-heparin 1,000 U/ev/hour for 48 hours and calcium-heparin 3,000 UI/10 Kg/12 hours from the third day to discharge...

Variability in precordial lead placement is a recognized source of electrocardiographic inaccuracy and lack of reproducibility. In an attempt to reduce error, we evaluated a new device to facilitate and guide precordial lead placement. This study involved three phases: (1) comparison of device-guided electrocardiogram with ECGs obtained by deliberate misplacement of precordial leads on the same patient; (2) electrocardiograms obtained by using the precordial lead device versus those obtained by standard technician methods; (3) reproducibility of precordial electrocardiographic leads between two technicians using the device to guide lead placement...

Two hundred consecutive patients undergoing coronary artery bypass for stable and unstable angina pectoris were followed clinically 3 to 53 months (mean 27) and with serial electrocardiograms (ECG's) 3 to 43 months (mean 18.5) postoperatively. Complete (twelve lead) resting ECG data including preoperative, early postoperative (in hospital), and late (post hospital) studies were available in 98 per cent (196/199) of hospital survivors. A total of 2,304 ECG's were examined by two cardiologists for a total follow-up of 3,629 patient months...