P101 LEFT VENTRICULAR MASS INDEX (LVMI) IS UNLIKELY TO NORMALISE WITH TREATMENT USING CURRENTLY RECOMMENDED BLOOD PRESSURE TARGETS

Background and Objectives: LVMI is one of the strongest predictors of cardiovascular events. However, it's unclear whether current blood pressure (BP) targets normalise LVMI relative to a truly normotensive population. We therefore compared achieved LVMI in a younger cohort of hypertensive patients (< 55 years) treated for one year to conventional blood pressure targets (< 140/90 mmHg) versus the LVMI of a truly normotensive age-matched healthy population from the UK Biobank (BP ≤ 120/80 mmHg). Methods: The normotensive cohort comprised 101 treatment-naïve men (mean ± SD age: 52 ± 2 years, BP: 112 ± 7/68 ± 7 mmHg) from 77,983 UK Biobank participants who had undergone cardiac Magnetic Resonance Imaging (cMRI) to determine LVMI. The treated hypertensive cohort comprised 44 men from the TREAT CASP study* (mean age: 49 ± 6 years) who achieved mean BP of 129 ± 10/78 ± 8 mmHg after one-year treatment. LVMI in both cohorts was measured accurately via automated analysis of cMRI and manually reviewed for accuracy. Results: LVMI in Biobank cohort was 51.3 ± 6.0 g.m- 2 (95% CI: 50.1 to 52.4 g.m-2). In the hypertensive cohort, after one year of treatment, LVMI was reduced (59.2 ± 7.0 versus 56.0 ± 7.0 g.m- 2 , P <0.001) but remained higher than the Biobank cohort (56.0 ± 7.0 versus 51.3 ± 6.0 g.m- 2 , P <0.001). Mean LVMI of treated-hypertensive patients achieving truly normotensive BP (≤ 120/80 mmHg) was 52.7 ± 5.7 g.m- 2 (95% CI: 48.9 to 56.4 g.m- 2 ; n = 9). Conclusions: This study identified optimal cMRI LVMI for healthy middle-aged men. Antihypertensive treatment reduces but does not restore LVMI to normal levels, suggesting much lower BP targets than currently recommended are likely to be necessary to normalise LVMI in hypertensive patients. *Reference: Lacy, P. S., Jedrzejewski, D., McFarlane, E., & Williams, B. (2023). Blood pressure measurement modalities and indexed left ventricular mass in men with low-risk hypertension confirmed by ambulatory monitoring. Journal of Hypertension, 41(6), 941-950.