44 - cardiology case 1

A 56-year-old man presents with athlete's foot. You take the opportunity to assess his general health and find that he has a blood pressure of 146/94 which is the average of two recordings in your clinic. He is otherwise well, is a keen runner, non-smoker, urinanalysis is negative for glucose and protein. He is not taking any regular medication and he has no family history of cardiovascular disease.

You record a 12-lead ECG the result of which is shown.

What is the next most appropriate step in managing this man?

(Please select 1 option)

	a.Anticoagulate with warfarin
	b.Lifestyle advice and monitor BP
	c.Lifestyle advice, monitor BP and treat to target <>
	d.Refer to medical team with Acute Coronary Syndrome
	e.Request an Exercise Stress Test

the correct answer is c .

The ECG shows Left Ventricular Hypertrophy (LVH) which, in the context of a 56-year-old man presenting opportunistically with hypertension suggests that he already has Target Organ Damage. This would place his 10 year cardiovascular risk at greater than 20% and he should probably therefore start on treatment for his blood pressure. The JBS 2: Joint British Societies' guidelines on prevention of cardiovascular disease in clinical practice published in December 2005 says:

"People with persistent blood pressure elevation > 160 mm Hg systolic and/or > 100 mm Hg diastolic are at sufficiently high CVD risk on the basis of blood pressure levels alone to require drug therapy to reduce their blood pressure. People with sustained systolic blood pressures > 140 but <= 160 mm Hg systolic and/or diastolic blood pressures > 90 but <= 100 mm Hg and clinical evidence of CVD or diabetes or target organ damage or a total CVD risk > 20% should be considered for blood pressure lowering drug therapy."

Evidence of target organ damage includes heart failure, established coronary heart disease, stroke or TIA, peripheral arterial disease, abnormal renal function (raised creatinine or proteinuria / microalbuminuria), hypertensive or diabetic retinopathy or left ventricular hypertrophy on the ECG.

This ECG shows typical changes of left ventricular hypertrophy with large voltages in the chest leads, associated ST depression and T wave inversion (this is called a 'strain pattern').

There are many different criteria for LVH.

Sokolow + Lyon (Am Heart J, 1949;37:161)

• S V1+ R V5 or V6 > 35 mm

Cornell criteria (Circulation, 1987;3: 565-72)

• SV3 + R avl > 28 mm in men

• SV3 + R avl > 20 mm in women

Framingham criteria (Circulation,1990; 81:815-820)

• R avl > 11mm, R V4-6 > 25mm

• S V1-3 > 25 mm, S V1 or V2 +

• R V5 or V6 > 35 mm, R I + S III > 25 mm

Romhilt + Estes (Am Heart J, 1986:75:752-58)

• Point score system

It is important to remember that the 12-lead ECG is very specific for diagnosing LVH but not very sensitive. Therefore if the voltage changes of LVH are present on the ECG it is very likely to be due to LVH. However, in more than 90% of patients with LVH it will not be apparent on the ECG. Where LVH is discovered further investigations may be required to look for other end-organ damage or cardiac abnormalities. Depending on local expertise and resources referral to secondary care may be required.