Brachial Systolic Pressure Research Articles

Nitroglycerin has more favourable effects on left ventricular afterload than apparent from measurement of pressure in a peripheral artery

Nitroglycerin (0.3 mg) was administered sublingually to 14 patients undergoing cardiac catheterization, and pressure waves compared in the ascending aorta and brachial artery. After nitroglycerin, ascending aortic systolic pressure fell in all cases (by 6-44, average 22 mmHg) whereas brachial systolic pressure remained unchanged (in three) or fell to a lesser degree (4-33, average 12 mmHg). Diastolic pressure did not change significantly. Alterations in pressure and in wave contour were explained on the basis of arterial dilation, with reduction in wave reflection. Nitroglycerin reduces left ventricular afterload through arterial dilation as well as preload through venous dilation. This effect on afterload is not apparent from measurement of pressure in the brachial artery.

Collateral compensation of severe carotid stenosis

In 516 patients who had endarterectomies for unilateral severe carotid stenoses, arteriography demonstrated no contralateral severe stenoses or occlusions. Pre and postoperative ocular pneumoplethysmography (OPG-Gee) measured simultaneous bilateral ophthalmic systolic pressures (OSP). Immediately after each OPG test a brachial systolic pressure (BSP) was measured with a stethoscope, cuff and manometer. Bilateral ophthalmobrachial systolic pressure (OBSP) indices were calculated from the three pressures measured with the combined testing. Analysis of these OBSP data indicates that the severe stenoses were relatively well compensated in 314 of the 516 patients (61%) whereas there was limited collateral compensation in the remaining 202 patients (39%). The data also suggest that the latter group incurs a greater element of compensatory central hypertension, which is reversed by carotid endarterectomy.

A comparison of radial, brachial, and aortic pressures after cardiopulmonary bypass

Previous investigations have identified falsely low radial artery pressures after cardiopulmonary bypass (CPB). The present study investigates the relationship among radial, brachial, and aortic arterial pressures in 33 cardiac surgical patients following CPB. Two minutes after separation from CPB, clinically important (≥10 mmHg) underestimation of systolic aortic pressures occurred in 17 of 33 (52%) radial artery catheters, while occurring in seven of 33 (21%) brachial artery catheters. Radial artery mean pressure underestimated aortic mean pressure by ≥5 mmHg in 21 of 33 (61 %) patients two minutes after CPB, while an equivalent aortic-to-brachial artery mean arterial pressure difference occurred in nine of 33 (27%) patients. The incidence of aorticto-radial mean arterial pressure differences ≥5 mmHg decreased to 40% (four of ten patients) by ten minutes after CPB, although interpretation is complicated by decreased availability of aortic pressure measurements. Multivariate analysis failed to identify factors predisposed to central-to-peripheral pressure gradients. Radial and brachial arterial pressures were compared both before and after CPB in all 33 patients. Brachial artery systolic and mean pressures were higher than corresponding radial artery measurements two minutes after CPB ( P < 0.05), followed by gradual resumption of a normal brachial-to-radial pressure relationship over 60 minutes. Either vasospasm in the brachial and radial arteries or profound arteriolar vasodilation in the upper extremity might cause the observed central-to-peripheral arterial pressure differences. The progressive central-to-peripheral decrease in mean arterial pressure favors the latter mechanism. Since radial artery pressures reproduce aortic pressure unpredictably immediately after CPB, blood pressure should be measured more centrally (eg, ascending aorta or femoral artery) before initiating vasopressor therapy for hypotension upon separation from CPB. Brachial artery pressure underestimates post-CPB aortic pressure less frequently and less severely than radial artery pressure, but reproduction of aortic pressure was too inconsistent to warrant substitution of brachial artery catheters for radial artery catheters. Alternatives to radial artery pressures appear most advantageous for the first 20 minutes after CPB separation, but occasionally they facilitate accurate diagnosis of blood pressure abnormalities well beyond that period.

Noninvasive determination of healing of major lower extremity amputation: the continued role of clinical judgment

Various tests are used preoperatively to differentiate patients who require an above-knee amputation (AKA) from those whose vascular supply is adequate to heal a below-knee procedure (BKA). This 15-month study of 109 amputations compared four of these methods: segmental Doppler systolic pressure measurements, transcutaneous oxygen measurement (tcPo2), fluorescein angiography, and skin thermometry. There were 66 BKAs (85% healed primarily) and 43 AKAs (93% healed primarily). The actual level of amputation was determined by the operating surgeon without consideration of the preoperative test results, and the incidence of healing was then related to the test parameters. The average skin temperature at the amputation site was higher (93.7° F) in the group that healed primarily compared with those who required operative stump revision (89.9° F) (p < 0.001). The mean midcalf tcPo2 was also higher in the BKA group that healed (Po2 = 36.6 mm Hg) compared with those who failed (Po2 = 16.4 mm Hg) (p < 0.001). Qualitative skin fluorescence was less successful in differentiating success from failure. Of the 63 BKAs that fluorescein predicted would heal, eight failed (13%). Doppler pressures at the thigh, popliteal, midcalf, or ankle level were unreliable in predicting healing of a BKA. Formulation of indexes relating absolute pressures to the brachial systolic pressure did not improve the value of this examination. From this review it is concluded that the skin temperature and tcPo2 obtained at the site of proposed amputation were the most reliable prognostic noninvasive examinations. Depending on which test was used, routine application of the noninvasive predictors in this study as the sole determinant of amputation level would have resulted in an AKA in 17% to 60% of patients whose amputations otherwise would have healed at a lower level. Objective data can supplement clinical judgment but not replace it.

Variability of ankle and brachial systolic pressures in the measurement of atherosclerotic peripheral arterial disease.

The aim of this study was to determine the variability of measurements of ankle and brachial systolic pressures and ankle brachial ratios in order to assess their suitability for use in epidemiological studies of arterial disease in the lower limbs. Thirty-six subjects had repeat measurements taken by four observers on two separate days using a Doppler probe and random zero sphygmomanometer. The variability in the measurement of ankle systolic pressure was comparable to that for brachial systolic pressure. The 95% confidence limits of one measurement of the ankle brachial ratio was estimated to be +/- 16%, reducing to +/- 10% for the mean of four measurements taken by two observers on two days. Analysis of variance indicated that the variability in the measurement of ankle brachial ratios attributable to observers, days, timing of measurements on the same day, and repeat measurements was considerably less than the "biological" variability between subjects and between legs. These results suggest that repeatability of the ankle brachial ratio is such that a single measurement is suitable for most epidemiological studies of atherosclerotic peripheral arterial disease.

Age- and sex-related changes in the ratio between ankle and brachial systolic pressure in normal subjects.

The ratio between ankle (ASP) and brachial (BSP) systolic pressure was studied by using Doppler ultrasound in 198 normal subjects aged between twenty and ninety years: 97 males and 101 females. The ASP/BSP ratio decreased significantly with age both in males (r = -0.64; p less than 0.001) and in females (r = -0.72; p less than 0.001). In males, the decrease in the ratio with age was due to a significant decrease in ASP with age (r = -0.52; p less than 0.001), whereas BSP did not increase significantly with age. In females, a different result was observed, since only BSP (and not ASP) was significantly (and positively) correlated with age. In both sexes, the diameter of the terminal abdominal aorta measured by echocardiography was significantly increased with age, and full examination with Doppler ultrasound excluded any significant arterial stenosis of the lower limbs. The study provided evidence that age- and sex-related changes in arterial wave transmission do exist in normal subjects.

The ratio between ankle and brachial systolic pressure in patients with sustained uncomplicated essential hypertension.

1. The ratio between ankle (ASP) and brachial (BSP) systolic pressures was studied using Doppler ultrasound in 66 male subjects, 33 with sustained uncomplicated essential hypertension and 33 age-matched normal controls. 2. Based on covariance analysis, the ASP-BSP relationship was significantly different in the two populations, the ASP/BSP ratio (mean +/- SEM) being significantly lower in hypertensive subjects (106 +/- 1 vs 132 +/- 2; P less than 0.001). 3. While the ASP/BSP ratio was negatively correlated with age in normal subjects, no significant correlation was observed in hypertensive subjects. 4. The diameter of the terminal abdominal aorta measured by echography was significantly greater in hypertensive subjects, while full examination with Doppler ultrasound excluded any significant arterial stenosis of the lower limbs. 5. The study suggested that, in patients with sustained uncomplicated essential hypertension, the lower ASP/BSP ratio is related to changes in arterial wave transmission.

Long-term results of surgical repair of coarctation of the aorta--evaluation by exercise test.

Thirty-six patients have been operated on for coarctation of the aorta. The age at operation ranged from 4 to 45 years with a mean of 14 years. Preoperative systolic blood pressure (BP) was above the normal mean + 2 SD in 34 (94%) of the patients. The surgical techniques used for correction of coarctation were: resection and end-to-end anastomosis (50%), resection and graft interposition (25%), patch graft angioplasty (22%) and subclavian artery to descending aorta bypass graft (3%). There was no hospital mortality. Systolic BP measured on hospital discharge available in 30 patients showed an average decrease of 26 mm Hg. The mean follow-up period in 16 of 30 patients (53%) was 7.2 years. All of these patients had a further decrease in systolic BP, and in 14 of 16 (87%) BP was within the mean + 2 SD. Twelve patients were examined in the vascular diagnostic laboratory to determine adequacy of the repair by hemodynamic measures. After average of 7.8 years following operation, all of them had ankle systolic BP higher than brachial systolic pressure; ankle BP did not drop after treadmill walking exercise and the directional Doppler velocity curves from the legs were normal. This study suggested that BP continued to decrease after hospital discharge. We were unable to demonstrate correlation between age at operation and decrease in BP. The adequacy of surgical repair can be assessed by mild effort stress test combined with ankle/arm ratio measurement and directional Doppler velocity curves.

Digital blood pressure and flow measurements in patients with primary Raynaud's phenomenon.

The value of digital systolic blood pressure (DBP) and flow (DBF) measurements for a quantitative diagnosis of Primary Raynaud's Phenomenon (PRP) was evaluated by comparing the results obtained in 10 patients and 20 normals. Digital skin temperature (DST), DBP and brachial systolic blood pressure (BBP) and DBF were measured at room temperature, at maximal vasodilatation and during cold provocation. At room temperature DST discriminates between normals and patients with an accuracy of 77%. On maximum vasodilatation no significant differences can be found in DBP and DBF between normals and patients. However, DBF was significantly different between male and females both in normals and in patients. During gradual cooling a decrease in DBF (a closing phenomenon) was observed both in normals and patients. In contrast DBP did not show a substantial pressure drop. Calculating digit to brachial systolic pressure indexes (DBI) a slight significant increase can be found during cold provocation both in normals and in patients. Only the DBI of digit IV during cold provocation showed a significant difference between normals and patients which resulted in an accuracy of 83%.

The Femorofemoral Graft

We measured the hemodynamic improvement after femorofemoral grafting and determined the five-year cumulative patency rate in 54 consecutive high-risk patients with unilateral iliac artery occlusion who had femorofemoral grafts who were studied with ankle and brachial systolic pressure measurements before and after operation and at six-month intervals. There were two early deaths and seven early graft failures (less than 30 days) with four amputations (all operated on for rest pain). All of the remaining 45 patients' conditions improved clinically and objectively. The resting pressure index (mean +/- SD) in claudicants (n = 23) increased from 0.35 +/- 0.15 to 0.67 +/- 0.20; in patients with severe ischemia (n = 31) it increased from 0.25 +/- 0.15 to 0.50 +/- 0.20. During the follow-up period (six months to ten years), there were eight deaths and 12 late graft failures (greater than 30 days). The late cumulative patency rate was 60% at five years. Hemodynamic improvement parallels clinical success and for these high-risk patients, the femorofemoral bypass is a satisfactory alternative to a more major operation.

Noninvasive measurement of femoral artery pressure for evaluating aortoiliac occlusive disease

Femoral systolic pressures measured by a compression technique (FSCP), were compared with proximal thigh systolic pressures (PTSP), for evaluation of aortoiliac occlusive disease. In phase I FSCP were measured by compressing the artery with a pressure cuff rolled into a cylinder and using disappearance of the profunda femoris Doppler signal (FSCP-D), or flattening of thigh plethysmographic waveforms (FSCP-P), as sensors. In normal extremities the compression techniques yielded false high values. The mean ratio of FSCP-D to brachial systolic pressure, FSCP-D/BSP, was 1.25 ± 0.06 and the mean FSCP-P/BSP was 1.37 ± 0.15, a value approximately equal to the mean PTSP/BSP, 1.38 ± 0.20. In patients with aortoiliac occlusive disease linear regression analysis revealed a good correlation between FSCP-D/BSP and direct intraoperative measurements of femoral/aortic systolic pressure, FSP/ASP, ( R = 0.79 and R 2 = 0.63), a fair correlation between FSCP-P/BSP and FSP/ASP ( R = 0.49, R 2 = 0.24) but a poor correlation between PTSP/BSP and FSP/ASP ( R = 0.35, R 2 = 0.12). In phase II studies a soft bladder was used for arterial compression. In normal extremities the mean FSCP-D/BSP was 1.07 ± 0.06, close to the predicted normal value of 1.00. In a second group of patients with occlusive disease a better correlation was observed between values of FSCP-D/BSP and FSP/ASP ( R = 0.91, R 2 = 0.82), than any of the correlations of noninvasive measurements with direct intraoperative values of FSP/ASP obtained in the first phase of the study.

Noninvasive penile arterial evaluation in120 males with erectile dysfunction

One hundred twenty males referred to a hospital-based Medical Sexology Programfor evaluation of erectile dysfunction had, as part of that workup, a noninvasive penile arterial assessment which included determination of (1) blood pressure in each of the six penile arteries, (2) patency of each cavernosal artery, and (3) brachial blood pressure. The systolic pressures in each of the six penile arteries were averaged and divided by the brachial systolic pressure to determine the penile brachial index (PBI). When a PBI of 0.75 or less was correlated with a history of myocardial infarction, coronary artery bypass, or cerebral vascular accident, a P value of 0.069 resulted, certainly suggesting that; each is a manifestation of arterial disease.

The relationship between aortoiliac hemodynamics and femoral pulsatility index

The relationship between systolic pressure and Doppler ultrasonic velocity waveform characteristics, both monitored at the common femoral artery, was investigated in 35 limbs of patients with arterial occlusive disease of varying severity and location. Intraarterial femoral systolic pressure, expressed as a ratio of the brachial systolic pressure, was measured at rest (F/B rest) and during postocclusive reactive hyperemia (F/B hyp). Resting femoral Doppler audio signals were displayed on a fast Fourier audiofrequency spectrum analyzer. Velocity waveforms were described numerically by calculation of pulsatility index (PI), defined as the ratio of maximum waveform frequency excursion to mean forward frequency. F/B rest values ranged from 0.71 to 1.29. Although there was a direct relationship between PI and the extremes of F/B rest, the fit of the regression line to the observed data was poor ( r 2 = 0.38) because PI varied widely in association with values of F/B rest > 0.9. However, PI correlated well ( r 2 = 0.73, P < 0.001) with the magnitude of percentage fall in F/B hyp as an inverse exponential function [ y = (6.91)(0.97) − x ]. Although this correlation was satisfactory in limbs with occluded ( r = −0.75) as well as patent ( r = −0.86) superficial femoral arteries (SFA), the slopes of these two regression curves tended to be slightly different ( P = 0.07). These results suggest that aortoiliac pressure dynamics can be estimated noninvasively from resting common femoral PI. The accuracy of the estimate may be marginally enhanced if SFA patency status is taken into account.

Clinical-angiographic correlation of ophthalmodynamometry in suspected carotid artery disease. Prospective study.

A prospective, clinical study of patients with suspected carotid artery disease compared the accuracy of compression and suction ophthalmodynamometry (ODM) with carotid artery stenosis determined by arteriography. Results were analyzed with respect to current criteria for classification and determination of "substantial" carotid artery disease. The best correlation for both procedures with arteriography was a ratio of the corrected intraocular pressure to the systolic brachial pressure. Both suction and compression ODM findings are equally accurate, with levels approaching 80%; however, neither test is sensitive enough to be used alone as a screening technique. Arteriography remains the best procedure for the determination of carotid artery disease.

Diagnostic accuracy of ocular pneumoplethysmography attachment for pulse volume recorder.

The ocular pneumoplethysmography (OPG) attachment for the Life Sciences Pulse Volume Recorder (OPG-LS) is a widely distributed instrument, but no results have been published on its accuracy in diagnosing carotid artery lesions. One hundred twelve patients were studied with the OPG-LS using lateralizing criteria and a curve of ophthalmic artery systolic pressure (OAP) to brachial systolic pressure (BP) for normal carotid arteries, which served as a discriminant between normal and stenotic vessels. Two hundred nineteen carotid arteries were visualized on arteriography and percentage of diameter stenosis was measured. Lateralizing criteria by themselves gave poor diagnostic accuracy, but when combined with OAP-BP data, positive diagnosis was made for lesions having greater than 60% diameter stenosis in 89.6% of patients and 80.8% of arteries. False-positive results for 0% to 30% diameter stenotic lesions occurred in 11.1% of arteries and in 13.6% of patients.

Aortoplasty Compared with Resection for Coarctation of the Aorta in Young Children

We repaired coarctation of the aorta in a group of 18 children less than 3 years old, using either resection with end-to-end anastomosis (8 patients, Group 1) or patch graft aortoplasty (10 patients, Group 2). The two groups were similar preoperatively in age, pressure difference between proximal and distal aorta (ΔP AO), and severity of aortic arch hypoplasia. Three patients, all less than 2 months old, died early postoperatively. Among the survivors, the right brachial artery systolic pressure was significantly higher in Group 1 (133.1 ± 7.0 mm Hg) (mean ± standard error of the mean) than in Group 2 (102.5 ± 7.2 mm Hg) ( p < 0.05). The ΔP AO was significantly higher in Group 1 (33.0 ± 7.5 mm Hg) than in Group 2 (5.1 ± 2.3 mm Hg) ( p < 0.01). Three patients in Group 1 required reoperation and were treated with patch graft aortoplasty; relief of ΔP AO was complete in 2. Patch graft aortoplasty is more effective than resection in reducing proximal aortic systolic pressure and in relieving ΔP AO in infants and small children with coarctation of the aorta.

Clinical, hemodynamic and metabolic responses during pacing in the supine and sitting postures in patients with angina pectoris

Hemodynamics during sinus rhythm and pacing-induced angina were studied in the supine and sitting positions in 12 patients with coronary artery disease. During sinus rhythm, left ventricular end-diastolic pressure, cardiac index, stroke index and left ventricular stroke work index were lower and heart rate was higher in the sitting position. During pacing, left ventricular end-diastolic pressure, stroke index and left ventricular stroke work index decreased, whereas pulmonary arterial mean pressure, mean pulmonary capillary wedge pressure and brachial arterial systolic and mean pressure remained unchanged in both positions. During pacing, angina was experienced by 12 patients in the supine and 10 patients in the sitting position. Chest pain was less severe and the pacing rates required to induce angina were higher in the sitting position (159 ± 3versus 132 ± 4 beats/min, P < 0.001). Comparison of data during pacing revealed lower values for left ventricular end-diastolic pressure, cardiac index, stroke index and left ventricular stroke work index, and higher values for heart rate and rate-pressure product in the sitting position; brachial arterial systolic and diastolic pressure, pulmonary arterial mean pressure and mean pulmonary capillary wedge pressure were similar in the two positions. In the immediate postpacing period, left ventricular end-diastolic pressure was lower in the sitting than in the supine position. Although the pacing threshold for angina was higher and the left ventricular end-diastolic pressure lower in the sitting position, myocardial lactate uptake was more often abnormal in this posture.

Nicotinic acid treatment of skin disorders

Nicotinic add treatment of cutaneous disorders of vascular origin of the lower extremities has been widely proposed (Winkelmann et al, 1974; Physicians Desk Reference, 1976) but this therapy has not been subjected to a controlled critical evaluation. Since the therapeutic effect of nicotinic acid is proposed to be relaxation of vascular smooth muscle, we undertook to examine the effect of nicotinic acid on the pretibial arteriolar pressure in maximally vasodilated skin (Nickerson, 1970). We examined six patients with stasis dermatitis. The patients were given nicotinic acid, 100 mg four times daily, for 2 weeks and placebo, four times daily for 2 weeks in a double-blind crossover fashion. The pretibial arteriolar pressure in maximally dilated skin was measured using a modification of the method of Chavatzas & Jamieson (1974). This technique consists of visualizing a histamineinduced flare through a transparent window in a sphygmomanometer cuff. The pressure at which the flare reappeared after occlusion was recorded. This method correlated well with xenon-washout studies (Chavatzas & Jamieson, 1976). The pretibial arteriolar pressure and the ratio of pretibial arteriolar pressure to brachial systolic pressure were examined at weekly intervals during nicotinic acid treatment and control (placebo) periods. We investigated the pretibial arteriolar pressure and the ratio of pretibial arteriolar pressure to brachial systolic pressure after a single dose of nicotinic acid, 100 mg by mouth. We also monitored the degree of cutaneous involvement, viz., a subjective quantification of dermatitis. We examined the fasting sera at weekly intervals for changes in triglycerides and cholesterol. Finally, one of us recorded the incidence of side effects. Since flushing was felt to be so common, the tabulator of side effects was not involved in the collection of any of the other data. In analysis of the data we foimd no consistent changes in pretibial arteriolar pressure, brachial systolic pressure, their ratio, cutaneous lesions, or serum lipids. Flushing was reported by all patients. Pruritus and nausea with occasional emesis were also reported by some patients. In summary, we found no effect of nicotinic acid on the pretibial arteriolar pressure, which should reflect the proposed therapeutic relaxation of vascular smooth muscle. The general use of nicotinic acid treatment for cutaneous disorders of vascular origin must remain questionable until further studies are done. (Author's note: Data available upon request.)

Preoperative estimation of run off in patients with multiple level arterial obstructions as a guide to partial reconstructive surgery.

Preoperative measurements of direct femoral artery systolic pressure, indirect ankle systolic pressure and direct brachial artery systolic pressure were carried out in nine patients with severe ischemia and arterial occlusions both proximal and distal to the ingvinal ligament. The pressure-rise at the ankle was estimated preoperatively by assuming that the ankle pressure would rise in proportion to the rise in femoral artery pressure. Thus it was predicted that reconstruction of the iliac obstruction with aorta-femoral pressure gradients from 44 to 96 mm Hg would result in a rise in ankle pressure of 16--54 mm Hg. The actual rise in ankle pressure one month after reconstruction of the iliac arteries ranged from 10 to 46 mm Hg and was well correlated to the preoperative estimations. In conclusion, by proper pressure measurements the run-off problem of multiple level arterial occlusions can be evaluated. Thus the result of successful partial reconstruction can be assessed preoperatively.

Calf blood flow and ankle systolic blood pressure in intermittent claudication monitored over five years.

The response of calf blood flow and ankle blood pressure to 2 minutes of ischemic exercise were recorded every 6 months over a 5-year period in 9 patients with intermittent claudication who were treated conservatively on a regime including alpha tocopherol. No statistically significant change was noted in the pattern of the calf blood flow response over this period. Statistically significant (P less than 0.05) increases in resting and minimal postexercise ankle systolic pressures were partially attributable to a concomitant increase in central arterial pressure as indicated by brachial systolic pressure. Results from 18 patients over 1 year and from 14 patients over 2 years are consistent with these findings. The evidence presented suggests that the arterial disease process was stable over this period.