Renal Denervation and International Registry Data: Where Are We Now?

Renal denervation in hypertension: An updated meta-analysis of the randomized controlled trials

BACKGROUND

Radiofrequency or ultrasound renal denervation (RDN) has shown conflicting results when used as an adjunctive option for hypertension management in randomized controlled trials (RCTs).

METHODS

We searched Pubmed, MEDLINE, and other online databases for RCTs comparing RDN versus sham-control procedures in patients with uncontrolled or resistant hypertension. The endpoints of interest were 24-h ambulatory (AMB) blood pressure (BP), daytime AMB BP, and office BP. We performed a random-effects meta-analysis using the inverse variance method to estimate mean difference (MD) with a 95% confidence interval (CI).

RESULTS

Nine studies with 1643 patients were included in the final analysis. The mean follow-up was 5 months. As compared with the sham-controlled group, RDN was associated with a significant decrease in 24-h AMB BP (systolic [MD -4.20; 95% CI -5.36 to -3.03; p < 0.00001], diastolic [-2.38; -3.42 to -1.35]), and daytime AMB BP (systolic: -5.11; -6.75 to -3.47, diastolic: -2.88; -3.91 to -1.85). Similarly, office BP was reduced with RDN (systolic: -5.46; -7.12 to -3.81; diastolic: -3.17; -4.23 to -2.12) when compared with placebo.

CONCLUSION

Our meta-analysis shows that RDN is associated with a significant reduction in the 24-h AMB BP, daytime AMB BP, and office BP.

The Predicament of Surgical Correction of Tetralogy of Fallot

Surgery for tetralogy of Fallot has a long history, which may be described as both a success story and a failure story. It is a success story because prognosis without surgery is very poor, but surgery makes it possible for affected babies to reach adulthood and lead productive lives. It is a failure story, however, since we still cannot cure this condition; we can only palliate it as illustrated in the sobering long-term outcome of affected patients. In this review article, we aim to explore the reason for this failure. This may be summed up in terms of the nature of the obstruction to the right ventricular outflow tract, which characterizes this malformation and must be relieved. This obstruction has several possible components, but none may be eliminated without harming the ventricle. There seems to be no 'extra' muscle band in tetralogy of Fallot that may be dispensed with without undermining ventricular function; every muscle band that is there should be there, just like in the normal heart, except that these are thicker than normal and somewhat displaced in tetralogy of Fallot, thus narrowing the right ventricular outflow tract. Consequently, ventricular function deteriorates with every muscle band that is cut, just like in the normal heart. We have to harm the heart in order to repair it. Every repaired Fallot is inevitably a damaged heart. Consequently, repair of this condition cannot be curative at present; it is palliative surgery.