Differential associations of ankle and brachial blood pressures with diabetes and cardiovascular diseases: cross-sectional study

Increased brachial systolic blood-pressure (BP) predicts diabetes (T2DM) but is not fully effective. Value of absolute ankle systolic BP for T2DM compared to brachial systolic BP is not known. Our objectives were to assess independent relationships of ankle-systolic BP with T2DM and cardiovascular disease in Europeans and south Asians. Cross-sectional studies of anonymised data from registered adults (n = 1087) at inner city deprived primary care practices. Study includes 63.85% ethnic minority. Systolic BP of the left and right-brachial, posterior-tibial and dorsalis-pedis-arteries measured using a Doppler probe. Regression models’ factors were age, sex, ethnicity, body mass index (BMI) and waist height ratio (WHtR). Both brachial and ankle systolic-BP increase with diabetes in Europeans and south Asians. We demonstrated that there was a significant positive independent association of ankle BP with diabetes, regardless of age and sex compared to Brachial. There was stronger negative association of ankle blood pressure with cardiovascular disease, after adjustment for BMI, WHtR and ethnicity. Additionally, we found that ankle BP were significantly associated with cardiovascular disease in south Asians more than the Europeans; right posterior tibial. Ankle systolic BPs are superior to brachial BPs to identify risks of Type 2DM and cardiovascular diseases for enhanced patient care.

Further evidence against the role renal medullary perfusion in short-term control of arterial pressure in normotensive and mildly or overtly hypertensive rats

Earlier evidence from studies of rat hypertension models undermines the widespread view that the rate of renal medullary blood flow (MBF) is critical in control of arterial pressure (MAP). Here, we examined the role of MBF in rats that were normotensive, with modest short-lasting pressure elevation, or with overt established hypertension. The groups studied were anaesthetised Sprague-Dawley rats: (1) normotensive, (2) with acute i.v. norepinephrine-induced MAP elevation, and (3) with hypertension induced by unilateral nephrectomy followed by administration of deoxycorticosterone-acetate (DOCA) and 1% NaCl drinking fluid for 3 weeks. MBF was measured (laser-Doppler probe) and selectively increased using 4-h renal medullary infusion of bradykinin. MAP, renal excretion parameters and post-experiment medullary tissue osmolality and sodium concentration were determined. In the three experimental groups, baseline MAP was 117, 151 and 171 mmHg, respectively. Intramedullary bradykinin increased MBF by 45%, 65% and 70%, respectively, but this was not associated with a change in MAP. In normotensive rats a significant decrease in medullary tissue sodium was seen. The intramedullary bradykinin specifically increased renal excretion of water, sodium and total solutes in norepinephrine-treated rats but not in the two other groups. As previously shown in models of rat hypertension, in the normotensive rats and those with acute mild pressure elevation (resembling labile borderline human hypertension), 4-h renal medullary hyperperfusion failed to decrease MAP. Nor did it decrease in DOCA-salt model mimicking low-renin human hypertension. Evidently, within the 4-h observation, medullary perfusion was not a critical determinant of MAP in normotensive and hypertensive rats.

Aortic acceleration as a noninvasive index of left ventricular contractility in the mouse

The maximum value of the first derivative of the invasively measured left ventricular (LV) pressure (+ dP/dtmax or P′) is often used to quantify LV contractility, which in mice is limited to a single terminal study. Thus, determination of P′ in mouse longitudinal/serial studies requires a group of mice at each desired time point resulting in “pseudo” serial measurements. Alternatively, a noninvasive surrogate for P′ will allow for repeated measurements on the same group of mice, thereby minimizing physiological variability and requiring fewer animals. In this study we evaluated aortic acceleration and other parameters of aortic flow velocity as noninvasive indices of LV contractility in mice. We simultaneously measured LV pressure invasively with an intravascular pressure catheter and aortic flow velocity noninvasively with a pulsed Doppler probe in mice, at baseline and after the administration of the positive inotrope, dobutamine. Regression analysis of P′ versus peak aortic velocity (vp), peak velocity squared/rise time (vp2/T), peak (+ dvp/dt or v′p) and mean (+ dvm/dt or v′m) aortic acceleration showed a high degree of association (P′ versus: vp, r2 = 0.77; vp2/T, r2 = 0.86; v′p, r2 = 0.80; and v′m, r2 = 0.89). The results suggest that mean or peak aortic acceleration or the other parameters may be used as a noninvasive index of LV contractility.

Endoscopic Doppler probe ultrasonography for detecting blood flow at post-endoscopic submucosal dissection ulcers of the stomach

Background and study aims The rate of early rebleeding after endoscopic submucosal dissection (ESD) for early gastric cancer ranges from 5 % to 38 %, despite application of preventive methods. Post-ESD rebleeding may be caused by “invisible” vessels that may not be detectable using ultrasonographic techniques. Recently, Doppler probe ultrasonography (DOP) has been used in endoscopy. Because little is known about the usefulness of DOP for decreasing the post-ESD rebleeding rate, we performed a preliminary case series study. Patients and methods Twelve patients underwent DOP for post-ESD ulcer evaluation after visible vessel coagulation. In this study, the novel DOP system used in the vascular surgery department was used. DOP-positive invisible vessels were shown as a pulse wave on the monitor. Results No (0 %) cases of post-ESD rebleeding occurred. Twenty invisible vessels were detected, and 13 were subjected to additional coagulation up to a depth of 3 mm. Mean DOP procedure time was 11.6 minutes (range: 8–18 minutes). In these latter cases, disappearance of the Doppler pulse wave was confirmed. No early rebleeding or other adverse events were experienced. Conclusion DOP is a safe and feasible method for detecting invisible vessels in post-ESD ulcers. Further investigation of the clinical relevance is warranted.