Improved cardiovascular risk stratification by a simple ECG index in hypertension.
BACKGROUND
We determined the prognostic value of the Cornell/strain [C/S] index, a simple electrocardiographic (ECG) index for left ventricular hypertrophy (LVH) defined by the presence of either a classic strain pattern or a Cornell voltage (sum of R in aVL + S in V(3)) >2.0 mV in women or 2.4 mV in men, or both.


METHODS
In a prospective, cohort study, 2190 initially untreated subjects (age 51 [+/- 12], 47% women) with essential hypertension without prior events were followed for up to 14 years (median, 5 years).


RESULTS
Prevalence of LVH at entry was 16.3% by using the C/S index, which yielded 33.6% sensitivity and 91.0% specificity. Other ECG criteria for LVH including Sokolow-Lyon, Romhilt-Estes, Framingham, Cornell, and strain alone, achieved a lower sensitivity and prevalence. Over the subsequent follow-up, 244 patients experienced a first major cardiovascular event. Event rate (x 100 person-years) was 2.01 in those without and 4.44 in those with LVH by the C/S index (P <.001). After adjustment for age, sex, smoking, and other counfounders, the C/S index identified subjects at increased risk of events (relative risk 1.76; 95% confidence interval 1.32-2.33). The C/S index achieved the highest population-attributable risk (16.1%) for cardiovascular events.


CONCLUSIONS
A simple ECG index that can be quickly measured from nondigital machines and without algorithms identifies LVH in a consistent proportion (16.3%) of hypertensive subjects. The LVH defined by such technique allows identification of individuals at high risk for cardiovascular events.
Verdecchia
Paolo
P
Dipartimento Malattie Cardiovascolari, Universita di Perugia, Ospedale R. Silvestrini, S. Andrea delle Fratte, 06122 Perugia, Italy. verdec@tin.it
Angeli
Fabio
F
Reboldi
Gianpaolo
G
Carluccio
Erberto
E
Benemio
Guglielmo
G
Gattobigio
Roberto
R
Borgioni
Claudia
C
Bentivoglio
Maurizio
M
Porcellati
Carlo
C
Ambrosio
Giuseppe
G
D000368:Aged; D002318:Cardiovascular Diseases / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D015331:Cohort Studies; D004562:Electrocardiography; D023381:Endpoint Determination; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D017379:Hypertrophy, Left Ventricular / Q000175:diagnosis / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D018570:Risk Assessment