An analysis of the ONTARGET^® and TRANSCEND^® study populations was performed to compare the effects of telmisartan, ramipril and the combination on left ventricular hypertrophy (LVH).

LVH is a reversible determinant of cardiovascular risk. Many types of antihypertensive agents, including diuretics, ß-blockers, calcium channel blockers, ACE inhibitors and ARBs, appear to promote regression of LVH. However, the relative effects of the ARB telmisartan and the ACE inhibitor ramipril are unknown.

The ONTARGET^® and TRANSCEND^® studies provided an opportunity to compare the effects of telmisartan monotherapy, ramipril monotherapy and the combination on LVH in a large, heterogeneous, high-risk population.

In the ONTARGET^® trial, patients were randomized to telmisartan 80 mg, ramipril 10 mg or the combination. Patients intolerant to ACE inhibitors were recruited to the TRANSCEND^® trial and received telmisartan 80 mg or placebo in addition to best standard care. The primary endpoint of the trials was the composite of CVD death, MI, stroke or hospitalization for congestive heart failure. The median follow-up was 56 months.

For the LVH analysis,¹ 90.4% of ONTARGET^®/ TRANSCEND^® patients (n=28,508) had a baseline 12-lead electrocardiogram (ECG) and at least one of the two scheduled follow-up ECGs at 2 and 5 years. 12.5% (n=3,565) of these patients had LVH at baseline.

Overall prevalence of LVH and new development of LVH were measured after 2 and 5 years. The relationship between LVH and risk factors and outcomes was also analyzed.

In TRANSCEND^® , telmisartan was found to significantly reduce the overall prevalence of LVH by 21% compared to placebo patients treated to the best standard of care (odds ratio [OR], 0.79; 95% confidence interval [CI] 0.68 to 0.91; P=0.0017).

Telmisartan also significantly reduced the risk of new onset of LVH by 37% compared to the control group (OR, 0.63; 95% CI, 0.51 to 0.79; P=0.0001) (Figure 1). This remained significant after adjustment for time of observation, achieved systolic BP, age, history of diabetes mellitus and hypertension and previous treatment with ACE inhibitors and ARBs.

Treatment with telmisartan did not significantly affect regression of pre-existing LVH (OR, 0.91; 95% CI, 0.70 to 1.19; P=0.49).

In ONTARGET^®, there was a trend towards less LVH with telmisartan as compared to ramipril (OR, 0.92; 95% CI, 0.83 to 1.01; P=0.07). No difference in LVH prevalence between the telmisartan group and telmisartan-ramipril combination group (OR, 1.01; 95% CI, 0.91 to 1.12).

In this large, long-term study of a broad range of high cardiovascular risk patients, telmisartan was shown to significantly prevent new-onset LVH, a known CHD risk factor, in patients at high CV risk. Telmisartan was also associated with significantly less LVH in those patients randomized to either telmisartan or placebo. These benefits were additive to best standard care.

Patients treated with telmisartan showed 8% less LVH during follow-up compared with ramipril, although this difference was not significant. One mechanism potentially leading to greater LVH regression with an ARB compared with an ACE inhibitor might be the overactivation of AT2 subtype receptors by angiotensin II during treatment with an ARB. AT2 subtype receptors are upregulated in hypertrophic hearts. These receptors might trigger antiproliferative and antifibrotic effects, opposing AT1 receptor stimulation of cardiac hypertrophy and remodeling.

Although fewer patients experienced LVH with telmisartan than with placebo in TRANSCEND^®, this difference did not translate into a difference in congestive heart failure,² a complication predicted by LVH and its changes over time. Similarly, although 8% fewer patients experienced LVH with telmisartan than with ramipril in ONTARGET^®, this difference did not affect outcome.3 This may have been because of the inadequate time for translation of the gradual LVH reduction into harder clinical events.

Pritor^®/Kinzalmono^® is indicated for the treatment of essential hypertension and for the reduction of cardiovascular morbidity in patients with:



PritorPlus^®/Kinzalkomb^® is indicated in patients whose blood pressure is not adequately controlled on telmisartan alone.