Effectiveness of Renal Denervationprevious Myocardial Infarction and Resistant Hypertension

Background Recent trials have confirmed the safety and efficacy of catheter–based renal denervation (RDN) as nonpharmacological treatment in resistant hypertension in the presence of concomitant antihypertensive therapy. Aim we report data of preliminary experience with RDN (Symplicity Spyral renal denervation system, Medtronic Inc.) in patients with resistant hypertension and high risk condition (previous myocardial infarction treated with myocardial revascularization). Methods We analyzed 8 patients (5 M/3 F) mean aged 70±8 years, with resistant hypertension (treated at least with 4 antihypertensive drugs, including a diuretic, at maximally tolerated doses, without reaching the therapeutic target) who were previously scheduled in follow up (FU) program, after myocardial revascularization, and treated applying radiofrequency energy for blood pressure (BP) lowering. All participants had baseline assessments before RDN and repeat assessment at 3 months including medical history, ambulatory blood pressure monitoring (ABPM), and routine blood and urine tests. We analyzed changes between baseline and at 3 months. Statistical Analysis Normally distributed variables are presented as mean ± standard deviation (SD) and were compared by Student’s t–test for paired data. A p≤0.05 value was considered statistically significant. Results Median follow–up was 13,7 ± 0,7 months. The antihypertensive drugs used were as follows: beta–blockers, alfa–blockers, calcium channel blockers, angiotensin II receptor antagonists, ACE inhibitors, loop diuretics, thiazide diuretics, canreonate. A total of participants completed FU post–procedure. At 3 months, compared with baseline, systolic BP was reduced by −49,20±12,15 (from 175,15 ± 8,21 to 122,7 ±13,0) mmHg (P‹0.005) and diastolic BP reduced by −12,23±8,68 (from 88,70± 7,15 to 71,5 ±7,40) mmHg (P‹0.02). These levels were maintained over time. Renal function assessed by estimated glomerular filtration rate did not change statistically significantly, from 60.21 ± 7,2 to 63,5 ± 7,7 mL/min per 1.73 m2 (P‹0.06). Mean heart rate remained unchanged. At 3 months, participants were taking at least one less antihypertensive drug than at baseline (from 5 ± 1 to 3 ± 1) (P=0.006). Conclusions RDN results in a significant and robust reduction in both office and ambulatory systolic and diastolic BP at 3 months and also during FU after catheter–based RDN on less medication and without evidence of adverse consequences on renal function.