Amlodipine alters hemorheological parameters: Increased efficacy at the cost of edema?

Background Despite several decades of use of calcium channel blockers, the side effect of edema persists as a class effect, and its mechanism is unresolved. Amlodipine has effects on hemorheology (HR), and its hemodilutory property may partly contribute to its antihypertensive action. This aspect is not well studied, and the literature is sparse in this regard. Objective This experiment was planned to determine effect of a single-dose administration of amlodipine on HR parameters in normal human volunteers. Methods and results Amlodipine (5 mg) or S (-) amlodipine (2.5 mg) was administered to 27 normal human volunteers. Whole-blood viscosity (WBV) at different shear rates, plasma viscosity (PV), red cell rigidity (RCR), red cell aggregation (RCA), hematocrit (Hct), plasma hemoglobin, along with plasma drug concentration were determined at time intervals, t = 0, 4, 8, 12, and 24 h. Statistically significant reductions were observed at tmax = 4 h in WBV at shear rates of 0.512 s–1 (p < 0.005), WBV at shear rates of 5.26 s–1 (p < 0.01), PV (p < 0.05), and Hct (p < 0.01). At t = 8 h, as drug concentration reduced, some of the changes persisted and later slowly decreased with the decreasing drug concentration till t = 24 h. Red blood cell–related parameters such as RCA and RCR remained unaltered. WBV values at all shear rates, when corrected for Hct = 0.45, did not show deviation from their original values at any time. Conclusions Amlodipine causes a reduction in Hct and blood viscosity, along with hemodilution. These effects persist as long as the drug remains in plasma. Edema resulting from chronic dosing may be explained by the aforementioned effects. It is possible that antihypertensive action of the drug may be due to a combination of vasodilatation and an improvement in the HR properties.

A pilot study comparing two sites for incision during pacemaker implantation and their influence on the scar

Objective There are two most common incisions that are used during most pacemaker implantation procedures, with the first type of incision being inferior and parallel to the clavicle (Group C) and the second type of incision along the deltopectoral groove (Group D). We evaluated the scars resulting from the two types of incision to objectively evaluate the degree of superiority in cosmetic outcomes, between these two types of incisions. Methods Seventy-six patients who underwent left pre-pectoral pacemaker insertion were evaluated, close to 6 months after the date of the pacemaker implantation, using a simple scoring system based on atrophy, contour and colour of the scar. The likelihood of reduced severity in scar scores were compared between the two groups and the number of patients with elevation or inversion of the scar and with keloid formation were quantified. Results Seventy-six patients, with 47 belonging to the ‘Group C’ and 29 belonging to the ‘Group D’ were evaluated. The average length (C: 25 ± 2 mm; D: 24 ± 3 mm) and thickness (C: 25 ± 3 mm; D: 26 ± 2 mm) of the scars were not significantly different. The mean cumulative total scores in ‘Group C’ (1.98 ± 1.50) and ‘Group D’ (1.93 ± 1.31) were comparable. The odds ratio (OR) estimate showed that outcomes for atrophy (OR:0.73), contour (OR:0.53) and the cumulative total scores (OR:0.72) were also comparable. Conclusion This pilot study showed that the deltopectoral groove incision as a site of incision is comparable to the infraclavicular incision.

Routine health check-ups: A boon or a burden.

Healthcare provider institutions in India now offer structured health check-up ‘packages’ for routine screening of common diseases. While some tests included within their ambit are in keeping with international and Indian recommendations, some are entirely unwarranted. Unnecessary and inappropriate screening tests may cause more harm than benefit. Besides financial and resource burden, there may be over-diagnosis and over-treatment, psychological distress due to false-positive test results, harm from invasive follow-up tests, and false reassurance due to false-negative test results. Clinicians must ensure a net benefit from tests and interventions in order to efficiently deliver preventive services. We reviewed current screening guidelines for cardiovascular disease and common cancers, and surveyed multiple ‘packages’ provided at 8 centres in Mumbai, India. We put forth our recommendations for routine health screening in asymptomatic adults in India. Natl Med J India 2016;29:18–21