Clinical Diagnosis of Electrical Versus Anatomic Left Ventricular Hypertrophy

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Raja Selvaraj, JIPMER

Organization of the talk

  • LVH - Why are we interested ?
  • ECG identification of LVH
  • Anatomic LVH (Echo)
  • Disparity between ECG and Echo LVH
  • Determinants of ECG voltage
  • Prognostic importance of each

LV hypertrophy

Prognosis

  • More cardiovascular events
  • More total mortality
  • More sudden deaths

Evidence

  • 3 to 4 fold increase in CV and all cause mortality (Framingham Study - 1, 2)
  • Similar findings in other studies (3, 4)
  1. Kannel et al. Electrocardiographic left ventricular hypertrophy and risk of coronary heart disease. The Framingham study. Ann Intern Med. 1970;72:813–822. https://www.ncbi.nlm.nih.gov/pubmed/4247338
  2. Kannel et al Left ventricular hypertrophy by electrocardiogram. Prevalence, incidence, and mortality in the Framingham study. Ann Intern Med. 1969;71:89–105. https://www.ncbi.nlm.nih.gov/pubmed/4239887
  3. Kannel et al. Precursors of sudden coronary death. Factors related to the incidence of sudden death. Circulation. 1975;51:606–613 https://www.ncbi.nlm.nih.gov/pubmed/123182
  4. Rautaharju PM et al. Electrocardiographic left ventricular hypertrophy and the risk of adverse cardiovascular events: A critical appraisal. J Electrocardiol. 2014;47:649–654 https://www.ncbi.nlm.nih.gov/pubmed/25012077

LVH and arrhythmias

  • 2 to 3 fold increase in risk with 1 mm increase in thickness

Ghali JK, Kadakia S, Cooper RS, Liao YL. Impact of left ventricular hypertrophy on ventricular arrhythmias in the absence of coronary artery disease. J Am Coll Cardiol. 1991;17:1277–1282. https://www.ncbi.nlm.nih.gov/pubmed/1826691

ECG identification of LVH

Criteria

  • Voltage alone
    • Sokolow-Lyon, Cornell
  • and duration
    • Cornell voltage-duration product
  • and other abnormalities
    • Romhilt-Estes score

Electrocardiogram changes associated with cardiac chamber hypertrophy: A scientific statement from the American Heart Association Electrocardiography and Arrhythmias Committee, Council on Clinical Cardiology; the American College of Cardiology Foundation; and the Heart Rhythm Society. Endorsed by the International Society for Computerized Electrocardiology. J Am Coll Cardiol. 2009;53:992–1002. https://www.ncbi.nlm.nih.gov/pubmed/19281932

Sokolow-Lyon

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Anatomic LVH (Echo)

Echo LVH

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Correlation of ECG and Echo LVH

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Goldberger AL. A specific ECG triad associated with congestive heart failure. Pacing Clin Electrophysiol 1982;5:593–9.

Disparity

  • When anatomic LVH is considered gold standard
  • ECG has poor sensitivity
  • Specificity acceptable

Accuracy of ECG criteria (1, 2)

  • Compared to echo / MRI / autopsy
  • Low sensitivity - ~ 25%
  • Good specificity - ~ 95 %
  1. Pewsner D, Juni P, Egger M, Battaglia M, Sundstrom J, Bachmann LM. Accuracy of electrocardiography in diagnosis of left ventricular hypertrophy in arterial hypertension: Systematic review. BMJ. 2007;335:711. https://www.ncbi.nlm.nih.gov/pubmed/17726091
  2. Jain A, Tandri H, Dalal D, Chahal H, Soliman EZ, Prineas RJ, Folsom AR, Lima JA, Bluemke DA. Diagnostic and prognostic utility of electrocardiography for left ventricular hypertrophy defined by magnetic resonance imaging in relationship to ethnicity: The Multi-Ethnic Study of Atherosclerosis (MESA) Am Heart J. 2010;159:652–658. https://www.ncbi.nlm.nih.gov/pubmed/20362725

Determinants of ECG voltage

Factors that may affect voltage

  • Distance of heart from chest wall
  • Thickness of chest wall
  • Cancellation effects

ECG - Echo correlation

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RICHARD B. DEVEREUX, M.D., MALCOLM C. PHILLIPS, M.D., PAUL N. CASALE, M.D.,RICHARD R. EISENBERG, M.D., AND PAUL KLIGFIELD, M.D.. Geometric Determinants of Electrocardiographic Left Ventricular Hypertrophy. Circulation 67, No. 4, 1983.

Intracavitary blood volume

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BRODY DA. A theoretical analysis of intracavitary blood mass influence on the heart-lead relationship. Circ Res. 1956 Nov;4(6):731-8

Others

  • Cell to cell coupling (Connexin)
  • Changes in extracellular matrix
  • Changes in properties of ion channels
  1. Bacharova L, Plandorova J, Klimas J, Krenek P, Kyselovic J. Discrepancy between increased left ventricular mass and"normal" QRS voltage is associated with decreased connexin 43 expression in early stage of left ventricular hypertrophy in spontaneously hypertensive rats. J Electrocardiol. 2008;41:730–734. https://www.ncbi.nlm.nih.gov/pubmed/18358486

Electrical remodeling as a unifying hypothesis

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Rodriguez-Padial L, Bacharova L. Electrical remodeling in left ventricular hypertrophy-Is there a unifying hypothesis for the variety of electrocardiographic criteria for the diagnosis of left ventricular hypertrophy? J Electrocardiol. 2012;45:494–497 https://www.ncbi.nlm.nih.gov/pubmed/22809575

Greater genetic disposition to ECG LVH

Mayosi BM, Keavney B, Kardos A, Davies CH, Ratcliffe PJ, Farrall M, Watkins H. Electrocardiographic measures of left ventricular hypertrophy show greater heritability than echocardiographic left ventricular mass. Eur Heart J. 2002;23:1963–1971. https://www.ncbi.nlm.nih.gov/pubmed/12473259

Which is prognostically important?

Swedish study

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Sundstrom J, Lind L, Arnlov J, Zethelius B, Andren B, Lithell HO. Echocardiographic and electrocardiographic diagnoses of left ventricular hypertrophy predict mortality independently of each other in a population of elderly men. Circulation. 2001;103:2346–2351 https://www.ncbi.nlm.nih.gov/pubmed/11352882

Oregon SUDS

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Narayanan K, Reinier K, Teodorescu C, Uy-Evanado A, Chugh H, Gunson K, Jui J, Chugh SS. Electrocardiographic versus echocardiographic left ventricular hypertrophy and sudden cardiac arrest in the community. Heart Rhythm. 2014;11:1040–1046 https://www.ncbi.nlm.nih.gov/pubmed/24657425

MESA study

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Bacharova L et al. Determinants of discrepancies in detection and comparison of the prognostic significance of left ventricular hypertrophy by electrocardiogram and cardiac magnetic resonance imaging. Am J Cardiol. 2015;115:515–522.https://www.ncbi.nlm.nih.gov/pubmed/25542394

Treatment

  • Reduction of anatomic LVH improves outcomes (1)
  • Reduction of ECG LVH improves outcomes (2, 3)

Devereux RB et al. Prognostic significance of left ventricular mass change during treatment of hypertension. JAMA. 2004;292:2350–2356. https://www.ncbi.nlm.nih.gov/pubmed/15547162

Levy D et al. Prognostic implications of baseline electrocardiographic features and their serial changes in subjects with left ventricular hypertrophy. Circulation. 1994;90:1786–1793 https://www.ncbi.nlm.nih.gov/pubmed/7923663

Wachtell K et al. Regression of electrocardiographic left ventricular hypertrophy during antihypertensive therapy and reduction in sudden cardiac death: The LIFE study. Circulation. 2007;116:700–705 https://www.ncbi.nlm.nih.gov/pubmed/17664372

Conclusions

Conclusions

  • Intriguing relationship between ECG LVH and Echo LVH
  • ECG LVH and anatomic LVH are distinct phenotypes
  • Both are prognostically important in an independent fashion