Improvements in ECG accuracy for diagnosis of left ventricular hypertrophy in obesity

Abstract

ObjectivesThe electrocardiogram (ECG) is the most commonly used tool to screen for left ventricular hypertrophy (LVH), and yet current diagnostic criteria are insensitive in modern increasingly overweight society. We propose a simple adjustment to improve diagnostic accuracy in different body weights and improve the sensitivity of this universally available technique.MethodsOverall, 1295 participants were included—821 with a wide range of body mass index (BMI 17.1–53.3 kg/m2) initially underwent cardiac magnetic resonance evaluation of anatomical left ventricular (LV) axis, LV mass and 12-lead surface ECG in order to generate an adjustment factor applied to the Sokolow–Lyon criteria. This factor was then validated in a second cohort (n=520, BMI 15.9–63.2 kg/m2).ResultsWhen matched for LV mass, the combination of leftward anatomical axis deviation and increased BMI resulted in a reduction of the Sokolow–Lyon index, by 4 mm in overweight and 8 mm in obesity. After adjusting for this in the initial cohort, the sensitivity of the Sokolow–Lyon index increased (overweight: 12.8% to 30.8%, obese: 3.1% to 27.2%) approaching that seen in normal weight (37.8%). Similar results were achieved in the validation cohort (specificity increased in overweight: 8.3% to 39.1%, obese: 9.4% to 25.0%) again approaching normal weight (39.0%). Importantly, specificity remained excellent (>93.1%).ConclusionsAdjusting the Sokolow–Lyon index for BMI (overweight +4 mm, obesity +8 mm) improves the diagnostic accuracy for detecting LVH. As the ECG, worldwide, remains the most widely used screening tool for LVH, implementing these findings should translate into significant clinical benefit.

Optimized electrocardiographic criteria for the detection of left ventricular hypertrophy in obesity patients

“…Rider et al made an adjustment to the cut‐off value of the Sokolow‐Lyon index (+8 mm). This improved the sensitivity to 27% (specificity 93%) in their test cohort and 25% in their validation cohort . Also, Robinson et al designed a new criterion [RaVL + (BMI − 29) × 0.017], which improved the sensitivity to 42%, however, with a relatively decreased specificity of 83% .…”

Electrocardiographic criteria for left ventricular hypertrophy in aortic valve stenosis: Correlation with echocardiographic parameters

“…The body mass index has frequently been reported to be a disturbing factor in an ECG analysis (Abergel, Tase, Menard, & Chatellier, 1996;Nan, Jin-Xiu, Pei-Xuan, & Xue-Rui, 2017;Rider et al, 2016). The amplitude of the QRS complex is lower in obese individuals due to the considerably greater distance between the heart and electrodes.…”

Prognostic significance of body mass index‐adjusted criteria for left ventricular hypertrophy

“…Resting ECG was recorded on a Marquette MAC 12 system (Marquette Medical Systems, Milwaukee, Wisconsin), and data were automatically processed at a central core laboratory. Four ECG‐LVH criteria were used in the present analysis: The original Cornell criteria 20 —R in aVL + S in V3 ≥ 2800 µV in men or ≥2200 µV in women The original Sokolow‐Lyon criteria 21 —S in V1 + R in V5 or R in V6 ≥ 3500 µV The BMI‐adjusted Cornell criteria 14 —product of R in aVL + S in V3 and BMI> 60 400 µV kg m −2 The BMI‐adjusted Sokolow‐Lyon criteria 15 —S in V1 + R in V5 or R in V6 ≥ 3500 µV (add 400 µV if overweight, add 800 µV if obese) …”

“…However, the most commonly used criteria for ECG‐LVH 8 are less sensitive in patients with obesity, 9‐11 as body fat impedes the conduction of the electrical energy to the precordial leads 11‐13 . In response to this, novel criteria for ECG‐LVH that account for obesity have been developed and improve the sensitivity in obese individuals, nearing the sensitivity of traditional ECG‐LVH criteria in non‐obese individuals 10,14,15 …”