QRS voltage measurements in autopsied men free of cardiopulmonary disease: a basis for evaluating total QRS voltage as an index of left ventricular hypertrophy

Amyloid Burden Correlates with Electrocardiographic Findings in Patients with Cardiac Amyloidosis-Insights from Histology and Cardiac Magnetic Resonance Imaging

Cardiac amyloidosis (CA) is associated with several distinct electrocardiographic (ECG) changes. However, the impact of amyloid depositions on ECG parameters is not well investigated. We therefore aimed to assess the correlation of amyloid burden with ECG and test the prognostic power of ECG findings on outcomes in patients with CA. Consecutive CA patients underwent ECG assessment and cardiac magnetic resonance imaging (CMR), including the quantification of extracellular volume (ECV) with T1 mapping. Moreover, seven patients underwent additional amyloid quantification using immunohistochemistry staining of endomyocardial biopsies. A total of 105 CA patients (wild-type transthyretin: 74.3%, variant transthyretin: 8.6%, light chain: 17.1%) were analyzed for this study. We detected correlations of total QRS voltage with histologically quantified amyloid burden (r = -0.780, p = 0.039) and ECV (r = -0.266, p = 0.006). In patients above the ECV median (43.9%), PR intervals were significantly longer (p = 0.016) and left anterior fascicular blocks were more prevalent (p = 0.025). In our survival analysis, neither Kaplan-Meier curves (p = 0.996) nor Cox regression analysis detected associations of QRS voltage with adverse patient outcomes (hazard ratio: 0.995, p = 0.265). The present study demonstrated that an increased amyloid burden is associated with lower voltages in CA patients. However, baseline ECG findings, including QRS voltage, were not associated with adverse outcomes.

Total 12-lead QRS voltage in patients with spontaneous acute aortic dissection with an initiating tear in the ascending aorta

Because nearly all patients with acute aortic dissection have systemic hypertension, we examined electrocardiograms (ECGs) in 21 patients with spontaneous acute type A aortic dissection. An earlier study had shown that total 12-lead QRS voltage was the best criterion for determining left ventricular hypertrophy from the ECG. We measured total 12-lead QRS voltage in 21 patients with spontaneous (no previous cardiac or aortic operation) acute type A aortic dissection and operative repair. Using >175 mm as evidence of left ventricular hypertrophy, only 8 patients (38%) had hearts of increased mass. Total 12-lead QRS voltage corresponded slightly with age but not with body mass index. In conclusion, total 12-lead QRS voltage is not useful for diagnostic purposes in patients with acute type A aortic dissection undergoing operative repair.

Massive Cardiomegaly (>1000 g Heart) and Obesity

Described herein are certain clinical and morphologic findings in 9 patients who at necropsy had hearts weighing >1000 g, a weight approximately 3 times normal. With the exception of 2 patients with hypertrophic cardiomyopathy, the common finding in the remaining 7 patients was obesity. None had valvular heart disease, the previously described major cause of massive cardiomegaly. Thus, obesity needs to be added to the causes of massive cardiomegaly, a cause not previously recognized. Electrocardiograms in 4 patients disclosed high total 12-lead QRS voltage on the electrocardiogram in only one despite the massive cardiomegaly.

Comparison of total 12-lead QRS voltage in a variety of cardiac conditions and its usefulness in predicting increased cardiac mass

Echocardiography provides a more accurate method to determine increased cardiac mass than does electrocardiography. Nevertheless, most offices of physicians do not possess echocardiographic machines, but many possess electrocardiographic machines. Many electrocardiographic criteria have been used to determine increased cardiac mass, but few of the criteria have been measured against cardiac weight determined at necropsy or after cardiac transplantation. Such was the purpose of the present study. Cardiac weight at necropsy or after transplantation was determined in 359 patients with 11 different cardiac conditions, and total 12-lead electrocardiographic QRS voltage (from the peak of the R wave to the nadir of either the Q or the S wave, whichever was deeper) was measured in each patient. Even in hearts with massively increased cardiac mass (>1,000 g), the total 12-lead QRS voltage was clearly increased (>175 mm) in only 94%, but this criterion was superior to that of previously described electrocardiographic criteria for "left ventricular hypertrophy." Hearts with excessive adipose tissue infrequently had increased total 12-lead QRS voltage despite increased cardiac weight. Likewise, patients with fatal cardiac amyloidosis had hearts of increased weight but quite low total 12-lead QRS voltage. In conclusion, 12-lead QRS voltage is useful in predicting increased cardiac mass, but that predictability is dependent in part on the cause of the increased cardiac mass.

Carcinoid heart disease without the carcinoid syndrome but with quadrivalvular regurgitation and unsuccessful operative intervention

A 53-year-old woman is described who underwent mitral and aortic valve replacement and tricuspid valve annuloplasty for pure regurgitation at all 3 valve sites for unrecognized carcinoid heart disease without the carcinoid syndrome 22 days before death. Metastatic carcinoid was not recognized until necropsy, which disclosed a probable ovarian primary but with large hepatic metastases and left-sided cardiac involvement either greater than or equal to the right-sided involvement. Pulmonary hypertension, very unusual in carcinoid heart disease, persisted postoperatively and probably played a role in the patient's early death. Hepatic metastasis with ovarian primary is most unusual in this circumstance.

Electrocardiographic crotchets or common errors made in the interpretation of the electrocardiogram

Irritating errors are called crotchets. This paper discusses the following electrocardiographic crotchets: memorizing patterns rather than using basic principles, failure to use the electrocardiogram as a diagnostic tool, failure to correlate all available data, failure to appreciate the limitation of the computer interpretation, failure to appreciate the diagnostic value of P-wave abnormalities, the identification and misuse of abnormal Q waves, the misuse of left or right axis deviation of the QRS complexes, the misuse of the amplitude of the QRS complexes as a sign of left ventricular hypertrophy, identification of left ventricular hypertrophy, failure to identify uncomplicated and complicated bundle-branch block, failure to identify secondary and primary T-wave abnormalities, failure to identify secondary and primary S-T abnormalities, and lack of knowledge of the U waves.

Electrocardiographic prediction of left ventricular geometric patterns in patients with essential hypertension

BACKGROUND

The present study sought to determine the diagnostic value of electrocardiographic voltage criteria in predicting geometry patterns in patients with essential hypertension.

METHODS

Patients with essential hypertension (n=125) according to left ventricular mass index and relative wall thickness as determined by echocardiography were assigned in the following groups: normal geometry (N, n=50), concentric remodeling (CR, n=12), concentric hypertrophy (CH, n=28) and eccentric hypertrophy (EH, n=35). Each patient underwent 12-lead ECG followed by determination of conventional voltage criteria as well as peak to peak QRS lengths in each lead.

RESULTS

Voltage criteria such as Sokolow-Lyon, Cornell, Cornell product >2440, D1R+D3S >25 mm, and AVL R >11 mm could not significantly predict and discriminate geometric patterns of LVH. However, they all were very specific (range 97-100%) and showed very high positive predictive values (range 94-100%) for detecting abnormal geometry. DI peak >12 mm had a sensitivity 61%, specificity 67%, accuracy 63%, positive predictive value 81%, and negative predictive value 42% in predicting to differentiate CH from CR. Sum of the calculated values from the peak of the R to the nadir of the S wave in all limb leads >60 mm had sensitivity 68%, specificity 75%, accuracy 70%, positive predictive value 86% and negative predictive value 50% in predicting to differentiate CH from CR.

CONCLUSIONS

Conventional ECG voltage criteria could not significantly discriminate specific geometry patterns observed in patients with essential hypertension.

Thoughts about the ventricular gradient and its current clinical use (part II of II)

The concept of the ventricular gradient was conceived in the mind of Frank Wilson in the early 1930s. Wilson, a mathematical genius, believed that the calculation of the ventricular gradient yielded information that was not otherwise obtainable. The method of analysis was not utilized by clinicians at large because the concept was not easy to understand and because the method used to compute the direction of the ventricular gradient was so time consuming that clinicians could not use it. Grant utilized the concept to create vector electrocardiography, but he believed that if his method of analysis was used, it was not often necessary to compute the direction of the ventricular gradient. He did, however, describe an easy way to compute the direction of the ventricular gradient. The current major clinical use of the ventricular gradient is to identify primary and secondary T-wave abnormalities in an electrocardiogram showing left or right ventricular hypertrophy or left or right ventricular conduction abnormalities. In addition, the author uses the term ventricular time gradient instead of ventricular gradient in an effort to clarify the concept. Finally, the author discusses the possible clinical significance of a normally directed, but shorter than normal, ventricular time gradient, an attribute that has not been emphasized previously.

Distance correction in the electrocardiographic estimation of left ventricular mass

Assessment of the left ventricular mass (LVM) from electrocardiograms may be improved by the addition of clinical variables into a multivariate equation. As the heart-thorax distance may affect the results, its relationships with electrocardiographic and clinical data have been evaluated in a group of 220 subjects (53 +/- 15 years, 126 female, 175 without demonstrated heart disease) who were assessed for echocardiographic LVM and heart-thorax distance. Sokolow, Cornell, and total QRS voltage indexes were obtained. Multiple regression equations with LVM as the dependent variable were fit, with an ECG index, body mass index (BMI), age, and gender as the independent predictors. Each of the 3 ECG indexes, BMI, age, and sex was shown to be independent predictors of LVM, with the ECG and BMI contributing with most of the explanatory power. When added to the model, the distance from the interventricular septum to the precordium (septal-LVD) was not a predictor of LVM, but when BMI was withdrawn, septal-LVD became an independent predictor of LVM (P < .001). This was not observed when septal-LVD was substituted for any other clinical or ECG variable, thus suggesting that septal-LVD accounts for information contained in BMI but not in the remaining variables. In addition, the distance from the center of LV to the precordium (mid-LVD) achieved significance as an independent LVM predictor, although the coefficient of multiple determination (R) practically did not change. Almost identical results are obtained when LVM is indexed for body surface area. Body mass index supplies virtually all the information contained in the heart-thorax distance.

ECG Variations in College Athletes

At Georgia Institute of Technology, the sports preparticipation evaluation includes a cardiovascular questionnaire and careful examination of the heart, listening especially for systolic murmurs that intensify with Valsalva's maneuver and/or standing, which could indicate hypertrophic cardiomyopathy (1,2).

Time-voltage QRS area of the 12-lead electrocardiogram: detection of left ventricular hypertrophy

Identification of left ventricular hypertrophy (LVH) using 12-lead ECG criteria based primarily on QRS amplitudes has been limited by poor sensitivity at acceptable levels of specificity. Because the product of QRS voltage and duration, as an approximation of the time-voltage area of the QRS complex, can improve accuracy of the 12-lead ECG for LVH, we examined the diagnostic value of true time-voltage area measurements of QRS complexes from the standard 12-lead ECG. Standard 12-lead ECGs and echocardiograms were obtained in 175 control subjects without LVH and in 74 patients with regurgitant valvular heart disease and LVH defined by echocardiographic criteria (indexed LV mass >110 g/m2 in women and >125 g/m2 in men). Standard voltage criteria, voltage-duration products (voltage multiplied by QRS duration), and true time-voltage areas of the QRS were calculated for Sokolow-Lyon criteria (SV1 +RV(5/6)) and the 12-lead sum of voltage criteria. Test sensitivities were compared using gender-specific partitions with matched specificity of 98% in the 175 subjects without LVH. Measurement of the time-voltage area significantly improved sensitivity for both criteria. The 76% sensitivity of the 12-lead sum area and 65% sensitivity of Sokolow-Lyon area were significantly greater than the 54% sensitivity of the approximation of QRS area provided by each voltage-duration product (P<.001 and P=.021) and than the 46% and 43% sensitivities of the respective simple voltage criteria (each P<.001). Comparison of receiver operating characteristic curves confirmed the superior overall performance of time-voltage area criteria compared with both voltage-duration products and simple voltage criteria. These results suggest that use of time-voltage areas can dramatically improve identification of LVH by 12-lead ECG. Further study of this approach is needed to identify optimal criteria for LVH based on the time-voltage area measurements from the 12-lead ECG.

Improved detection of echocardiographic left ventricular hypertrophy using a new electrocardiographic algorithm

OBJECTIVES

The purpose of this study was to use the Framingham data base to devise and test an improvement in an electrocardiographic (ECG) voltage criterion for detecting left ventricular hypertrophy that is gender specific and adjusts for age and obesity.

BACKGROUND

Electrocardiographic detection of left ventricular hypertrophy has been receiving increasing attention. The "Cornell" ECG voltage, defined as the sum of voltages for the R wave of lead aVL and S wave of lead V3, has been shown to correlate strongly with echocardiographically estimated left ventricular mass. Because the magnitude of this voltage varies with both age and obesity, we have proposed a simple formula for its adjustment for these two variables.

METHODS

Using linear regression, the adjustment formula was estimated from data on 1,468 men and 1,883 women from the Framingham Heart Study cohort who were free of myocardial infarction and who had both an ECG and an echocardiogram recorded during the same clinic examination. A modified receiver operating characteristic curve method was used to compare sensitivities at the same specificity levels. The adjustment formula was estimated from one randomly chosen half of the study cohort and applied to the other half for evaluation.

RESULTS

Significant improvement in sensitivity for the detection of left ventricular hypertrophy was realized at all levels of specificity. At a specificity level of 98%, the adjustment increased the sensitivity of the Cornell voltage from 10% to 17% in men and from 12% to 22% in women. For severe hypertrophy, defined as a left ventricular mass > 3 SD above the gender-specific mean, the sensitivity increased from 23% to 38% for men and from 22% to 55% for women at a specificity level of 95%.

CONCLUSIONS

This approach can substantially enhance the utility of the ECG for the detection of left ventricular hypertrophy. If these results are validated in other population groups, this approach may prove valuable in the screening of hypertensive populations and for the monitoring of patients undergoing treatment for hypertension.

Serial electrocardiographic changes in idiopathic dilated cardiomyopathy confirmed at necropsy

Serial electrocardiographic changes in necropsy-proven idiopathic dilated cardiomyopathy are evaluated and a method of predicting heart weight using QRS amplitudes is described. In 34 patients with multiple electrocardiograms (mean 3/patient) progressive prolongation of PR interval (0.18 +/- 0.03 to 0.21 +/- 0.03, p less than 0.001) and QRS duration (0.10 +/- 0.02 to 0.13 +/- 0.03, p less than 0.0001) was noted. Progressive conduction abnormalities were common (82%). QTc interval and QRS- and T-wave axes did not change. In 50 patients with electrocardiograms within 60 days of death, total 12-lead QRS and V1 through V6 QRS amplitude correlated better with heart weight (r = 0.51, p less than 0.0001 and r = 0.55, p less than 0.0001) than the Estes-Romhilt score did. The mean total 12-lead QRS amplitude was 138 mm with a mean of 106 for V1 through V6. In 31 patients cardiac mass index was calculated and showed significant correlation with 12-lead and V1 through V6 QRS amplitudes (r = 0.68, p less than 0.0001 and r = 0.75, p less than 0.0001, respectively). The QRS amplitudes remained constant during the illness. By using total 12-lead QRS or frontal plane QRS amplitude, heart weight can be predicted as early as 2 years before death. Use of body surface area and QRS amplitude criteria increases the accuracy of heart weight prediction. Thus, progressive electrocardiographic changes are common in patients with idiopathic dilated cardiomyopathy and QRS amplitude criteria are more accurate in the prediction of left ventricular hypertrophy than standard criteria.

Idiopathic dilated cardiomyopathy: analysis of 152 necropsy patients

Certain clinical and cardiac necropsy findings are described in 152 patients aged 16 to 78 years (mean 45) with idiopathic dilated cardiomyopathy: 109 (72%) were men and 43 (28%) were women. Compared with the women, the men had a significantly (p less than 0.05) shorter mean duration of chronic congestive heart failure (CHF) (43 vs 69 months), a higher percentage of habitual alcoholism (40 vs 24%) and a higher mean heart weight (632 vs 551 g). The male to female ratio among the 58 known alcoholics was 7.3:1 and among the 70 known nonalcoholics, 1.5:1 (p less than 0.05). The mean duration of clinical evidence of CHF was similar among the known alcoholics and the known non-alcoholics (each 50 months). Of the 152 patients, 148 (97%) had clinical evidence of chronic CHF; in 114 patients it was the initial manifestation of idiopathic dilated cardiomyopathy, and in most it became intractable and caused death. The interval from onset of chronic CHF to death (known in 120 patients) ranged from 1 to 264 months (mean 54). Comparison of the 27 patients surviving greater than 72 months after onset of chronic CHF to the 64 patients surviving less than or equal to 36 months disclosed a significantly higher frequency in the longer survival group of older patients, of women, of habitual alcoholics, of patients with chest pain syndromes, diabetes mellitus, pulmonary emboli, of patients treated with warfarin and of patients with larger hearts at necropsy. Each of the 4 patients without chronic CHF died suddenly and sudden death was the initial manifestation of idiopathic dilated cardiomyopathy in them. An additional 33 patients also died suddenly, but each of them previously had had chronic CHF. Of the 79 patients (of the 131 for whom information was available) with either pulmonary or systemic emboli or both, 67 (85%) had either right- or left-sided thrombi or mural endocardial plaques or both, whereas of the 52 patients without emboli, 36 (69%) had intracardiac thrombi or plaques (p less than (0.05). Electrocardiograms in the last 6 months of life in 101 patients disclosed atrial fibrillation in 25; complete left (41 patients) or right (6 patients) bundle branch block or indeterminate intraventricular conduction delay (4 patients) in 51 patients; QRS voltage indicative of ventricular hypertrophy in 44 patients (left ventricular in 39 patients.(ABSTRACT TRUNCATED AT 400 WORDS)