What are the dangers if an electrocardiogram (ECG) is missed in a patient with newly diagnosed hypertension and left ventricular hypertrophy (LVH)?

Dangers of Missing ECG in Hypertensive Patients with LVH

Missing an ECG in a newly diagnosed hypertensive patient who has left ventricular hypertrophy means failing to identify a patient at several-fold increased risk for cardiovascular death, heart failure, stroke, and myocardial infarction—risks that persist even after adjusting for other cardiovascular risk factors.

Why ECG is Essential in Newly Diagnosed Hypertension

Prognostic Significance of ECG-Detected LVH

• LVH detected by ECG is an independent predictor of major adverse cardiovascular events (MACE) and death, with hazard ratios ranging from 1.69 to 1.87 depending on whether detected by ECG alone or in combination with echocardiography 1

• ECG diagnosis of LVH predicts a several-fold increase in age- and risk factor-adjusted cardiovascular morbidity and mortality in asymptomatic patients with essential hypertension 2

• A 12-lead ECG should be part of the routine assessment of all hypertensive patients according to ESH/ESC guidelines, as it provides critical risk stratification even with its limited sensitivity 3

Specific Cardiovascular Risks When LVH Goes Undetected

Increased mortality and morbidity:

• Patients with undetected LVH face substantially elevated risks of cardiovascular death, heart failure, atrial fibrillation, and ischemic stroke 3
• The presence of ECG strain patterns (secondary ST-T abnormalities) indicates more severe LVH and even higher risk 4

Missed opportunities for risk stratification:

• ECG can detect left atrial abnormalities, which may be the earliest ECG sign of hypertensive heart disease and independently predict death, heart failure, atrial fibrillation, and ischemic stroke 3, 4
• ECG identifies arrhythmias including atrial fibrillation, which is a very frequent cause of stroke in hypertensive patients and requires anticoagulation 3

Inadequate treatment intensity:

• Without ECG documentation of LVH, patients may not receive appropriately aggressive blood pressure management
• LVH represents asymptomatic organ damage that should escalate treatment targets and medication choices 3

Clinical Utility Despite ECG Limitations

ECG Remains First-Line Despite Lower Sensitivity

• ECG sensitivity for LVH ranges from only 6-50%, but its specificity is high (70-99%), meaning when ECG detects LVH, it is usually real and carries significant prognostic weight 3, 5

• ECG is universally available, technically easy to perform, and highly specific, making it the cornerstone of LVH diagnosis in clinical practice 6

• Both ECG and echocardiography are efficient diagnostic tools for LVH and useful for long-term risk stratification—they provide complementary information 1

Key ECG Findings That Should Not Be Missed

Voltage criteria for LVH:

• Sokolow-Lyon index (SV1 + RV5 ≥3.5 mV), modified Sokolow-Lyon, RaVL >1.1 mV, or Cornell voltage QRS duration product (>244 mV*ms) 3, 7

High-risk ECG patterns:

• Strain patterns (lateral ST depression with T wave inversion) indicate more severe LVH and substantially higher risk 4, 7
• Left atrial abnormalities frequently accompany LVH and may appear before voltage criteria are met 4, 7

Other critical findings:

• Ischemic changes, conduction abnormalities, and arrhythmias including atrial fibrillation 3

The Role of Echocardiography

Echocardiography should be considered when ECG is abnormal or shows LVH:

• In hypertensive patients at moderate cardiovascular risk, echocardiography refines risk evaluation by detecting LVH undetected by ECG 3
• In patients with ECG evidence of LVH, echocardiography more precisely assesses the hypertrophy quantitatively and defines its geometry and risk 3
• Echocardiography is recommended in patients with hypertension and ECG abnormalities, or signs or symptoms of cardiac disease 3

However, ECG must come first:

• Additional echocardiographic evaluation for LVH is helpful for predicting long-term outcomes primarily in patients without LVH diagnosis by ECG 1
• The 2024 ESC guidelines recommend a 12-lead ECG as part of initial routine work-up for all patients with hypertension 3

Common Pitfalls

Assuming normal ECG excludes significant LVH:

• Due to low sensitivity (especially in obesity), a normal ECG does not rule out LVH 5
• Obesity dramatically decreases ECG sensitivity for detecting LVH 5

Missing early signs:

• Left atrial abnormalities may be the earliest ECG manifestation of hypertensive heart disease before voltage criteria are met 4

Failing to recognize high-risk patterns:

• Strain patterns carry particularly high risk and should prompt aggressive management 4, 7

Not performing ECG in all newly diagnosed hypertensive patients:

• This is a guideline-recommended routine test that should never be omitted 3