In light of the known incidences of malignant LVH and heart failure in Black patients, ECG can be vital to diagnostic decision-making and future care planning.

Article

Detecting LVH on ECG in Black Patients

It's well documented that left ventricular hypertrophy (LVH) is seen more frequently among Black patients than any other racial or ethnic group. In combination with disparities in care that marginalized populations experience, increased risk of LVH can contribute to heart failure, worsening outcomes, and mortality.

The known prevalence of LVH in Black patients indicates that LVH plus subclinical cardiac injury, as measured by troponin, exacerbates risks.1,2 Accordingly, cardiologists should be diligent about monitoring for and detecting LVH on ECG—particularly, malignant (biomarker-abnormal) LVH. Because the condition is largely asymptomatic, ECG is a critical high-specificity tool that should be part of the diagnostic workup.

Why Is There an Elevated LVH Risk Among Black Patients?

The contributors to this elevated risk may be multidimensional. Although there is relatively little known regarding which specific genetic traits may contribute to excess LVH, research identified several novel biological pathways specific to Black adults, including LKHA4 and fractalkine.3

Importantly, Black patients have an increased risk of hypertension, the most common cause of LVH. A spate of genetic variants linked to African heritage, such as those seen in the enzyme corin, may be contributors to high blood pressure and LVH. It's important to note that African ancestry was associated with LVH, while self-reported race was not, highlighting the genetic factors at play. Research found incidence and factors of LVH among Black Africans were similar to those of African Americans, with blood pressure cited as the primary determinant.4

Non-genetic causes of these higher incidences may include psychosocial and socioeconomic conditions that increase Black patients' risk of obesity and high blood pressure. Social determinants of health, including access to nutrition and healthcare, might all play a role in disease onset and progression, but more research is still needed to explore the extent of these environmental impacts on malignant LVH.

Identifying LVH on ECG: What to Look For

Several sets of LVH ECG criteria are used diagnostically.5 However, as opposed to voltage criteria alone, "electrocardiographic strain pattern identifies cardiac patients at higher risk of cardiovascular-related as well as all-cause morbidity and mortality."6

In research examining racial differences in LVH, investigators defined LVH on ECG through the Sokolow-Lyon criteria.2 However, other research noted that "Sokolow-Lyon and 12-lead voltage overestimate and Cornell voltage underestimates the presence in LVH in [Black patients]. However, these apparent ethnic differences in test performance disappear when ethnic differences in the distribution of ECG LVH criteria are taken into account."7

Additional research found that large voltage and anterior T-wave inversion are common in Black male athletes compared to white and West Asian male athletes.8

To further stratify LVH by malignance (and risk of heart failure), biomarker tests can also be used in the diagnostic workup. Lab tests showing high-sensitivity cardiac troponin-T exceeding 6 ng/L or N-terminal pro-B-type natriuretic peptides over 100 pg/mL indicate malignant LVH. In their analysis, Black patients had a three times greater prevalence of malignant LVH than white patients. Overall heart failure hazard ratios were 2.8 and .9 for malignant LVH and non-malignant LVH, respectively.2

To learn more about the power of the ECG in today's clinical landscape, browse our Diagnostic ECG Clinical Insights Center.

Managing and Preempting Heart Failure Risks

If malignant LVH is detected, heart failure risk management—including hypertension control—should be a priority. Other interventions, such as sodium-glucose cotransporter-2 inhibitors, may also help manage the risk, though more research is needed to explore the application of these therapies on LVH.

Additionally, researchers have noted the need for more investigation into opportunities to preempt malignant LVH altogether and deploy screening strategies that identify risk. Given the healthcare disparities that Black patients experience, blood pressure management in concert with addressing genetic, environmental, and other risk factors will be critical.

Ultimately, these insights demonstrate the need for more clinical diligence and surveillance of Black patients—particularly because both hypertension and LVH may not cause physical symptoms that would warrant a medical consult. In light of the known incidences of malignant LVH and heart failure in Black patients, ECG can be vital to diagnostic decision-making and future care planning in such cases.

References:

  1. Pandey A et al. Association of cardiac injury and malignant left ventricular hypertrophy with risk of heat failure in African Americans. Journal of the American Medical Association. Jan 2019; vol. 4 (no.1). https://jamanetwork.com/journals/jamacardiology/fullarticle/2718501
  2. Lewis A et al. Racial differences in malignant left ventricular hypertrophy and incidence of heart failure. Journal of the American Heart Association. March 2020; vol. 141 (iss. 12): 957-967. https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.119.043628
  3. Katz D et al. Multiomic profiling in Black and White populations reveals novel candidate pathways in left ventricular hypertrophy and incident heart failure specific to Black adults. Journal of the American Heart Association. May 2021; vol. 13 (iss. 3). https://www.ahajournals.org/doi/10.1161/CIRCGEN.120.003191
  4. Baldo P M et al. Prevalence and clinical correlates of left ventricular hypertrophy in Black Africans. High Blood Pressure & Cardiovascular Prevention. June 2018; vol. 25: 283-289. https://link.springer.com/article/10.1007/s40292-018-0267-y
  5. Healio. Left ventricular hypertrophy (LVH) ECG review. www.healio.com. https://www.healio.com/cardiology/learn-the-heart/ecg-review/ecg-topic-reviews-and-criteria/left-ventricular-hypertrophy-review
  6. Ogah O S et al. Electrocardiographic left ventricular hypertrophy with strain pattern: prevalence, mechanisms and prognostic implications. Cardiovascular Journal of Africa. Jan-Feb 2008; vol. 19 (iss. 1): 39-45. https://pubmed.ncbi.nlm.nih.gov/18320088/
  7. Okin P M et al. Ethnic differences in electrocardiographic criteria for left ventricular hypertrophy: the LIFE study. Losartan Intervention for endpoint. American Journal of Hypertension. Aug 2002; vol. 15 (iss. 8): 663-671. https://pubmed.ncbi.nlm.nih.gov/12160187/
  8. Wilson M G et al. Prevalence of electrocardiographic abnormalities in West-Asian and African male athletes. British Journal of Sports Medicine. Apr 2012: vol. 46 (iss. 5): 341-347. https://pubmed.ncbi.nlm.nih.gov/21596717/