Compression wraps as adjuvant therapy in the management of acute systolic heart failure: a pilot clinical trial

Background/Introduction

Current guidelines recommend targeting overall decongestion in management of patients with decompensated heart failure. With lower extremity edema among the most prevalent symptoms in patients admitted with decompensation, this often serves as a clinical target. Lower extremity compression wraps (LECW) are seldom used in the acute setting, with little data on efficacy in heart failure, despite serving as a cornerstone of chronic lymphedema management.

Purpose

Evaluate the efficacy of LECW as adjuvant therapy in management of HF with reduced ejection fraction (EF).

Methods

Open-label, randomized, parallel group controlled trial, with 2:1 randomization of adult patients with a history of HF and reduced EF less than 40% admitted to telemetry unit for intravenous (IV) diuretic therapy.

Results

A total of 32 patients were enrolled, with 29 patients completing the study; 19 (66%) in the control arm, and 10 (34%) in the intervention arm. There were no significant differences in baseline characteristics of the two groups. Patients in the intervention arm required less escalation of diuretic therapy (0 vs 5 patients, p=0.079), and less frequent use of continuous infusion therapy (0 vs 7 patients, p=0.027). Total days of IV diuresis was not significantly different between the two groups. Greater net reduction of edema was seen in the intervention group (1.5+ [1–2] vs 1+ [1–2], p=0.072), with fewer cases of acute kidney injury (1 vs 13, p=0.005). The intervention group scored significantly better on MLWHF (55.5 vs 65, p=0.021), including both the physical (17.5 vs 23, p<0.001) and emotional (5.5 vs 11, p<0.001) dimension scores. Overall LOS was shorter in the intervention group (3.5 [3–7] vs 6 [5–10] days, p=0.05). A Poisson regression model was used to examine the effect of intervention on LOS (IRR=0.62, 95% CI 0.44–0.86, p=0.005), suggesting an overall 38% shorter LOS.

Conclusion

In this open-label parallel group RCT, use of LECW resulted in less IV diuretic continuous infusion therapy, greater net reduction in lower extremity edema, reduced patient assessed HF burden, and shorter hospital LOS, with fewer rates of AKI. Trends toward fewer total days of IV diuresis, less escalation of diuresis, and greater reduction in edema were also observed. Larger scale clinical trials are needed to further establish LECW as efficacious adjuvant therapy in the management of acute heart failure.

Funding Acknowledgement

Type of funding sources: None.

Incremental prognostic value of SPECT CT based visual calcium score burden for outcomes prediction

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): Astellas Pharma US

Background

Coronary calcium is an important non-perfusion finding on SPECT CT attenuation correction (AC) and has been shown to help decrease equivocal interpretation and identifying atherosclerosis despite normal perfusion. Although correlations with measured calcium score have been good, an easy visual calcium score (VCS) for CT AC calcium and its prognostic value has not been well established. 

Purpose

We aimed to evaluate the role of VCS calculated from low-dose CT for AC in predicting outcomes stratified by SPECT (normal versus abnormal).

Methods

A retrospective data review of patients who underwent cardiac SPECT CT at our center from January 2009 -August 2012 with a mean follow up of 4.5 years. Baseline characteristics and outcomes were collected. VCS scoring was established as follows and was completed on all scans by three senior cardiology fellows. When not congruent, consensus with third reader was established. Presence of visual calcium in any of the following arteries was recorded as a score of 1 with VCS range 0-6: left main, left anterior descending, left circumflex, right coronary, ascending aorta, and descending thoracic aorta. Subjects were divided into 3 groups based on the VCS of <2, 2-4, and >4. Normal versus abnormal SPECT was defined as summed stress score/summed difference score of <4/<2 and > =4/> =2 respectively. Major adverse cardiac events (MACE) defined as presence of heart failure, myocardial infarction, and/or cardiac death.

Results

538 consecutive patients with SPECT CT were evaluated. Mean age was 63.3 years with 54% females. There were 463 (86%) normal SPECT and 75 (14%) abnormal SPECT. Using VCS, there was a statistically significant increase in the percentage of MACE over the period of follow-up with step wise increase in VCS severity in normal SPECT group (p-value = 0.001), although not significant in the abnormal MPI group (Figure 1). There was a higher mortality with increasing VCS in both normal and abnormal SPECT (p= <0.001 and p = 0.014 respectively). Using a multivariate logistic regression model in patients with normal SPECT, there were higher odds of death (OR 1.26) with every 1 point of VCS increase controlling for age, sex, baseline heart rate, history of dialysis, diabetes and stroke (95% confidence interval 1.09, 1.45; p-value = 0.002).

Conclusion

This study highlights the importance of factoring CT AC calcium in risk assessment of SPECT. CT AC calcium represents an easily available and important adjunctive risk marker during SPECT interpretation. A simple VCS as derived in this study can help with the additive risk stratification in both normal and abnormal SPECT and is of an incremental prognostic value for MACE. Clinicians interpreting SPECT should include coronary calcification on AC CT routinely in reports to help management and prognostication decisions. Our study shows that VCS can be a simple easily adopted tool for consistent reporting.

A new technique for study of impact of arterial elasticity on left ventricular mass in rats

We investigated possible links between left ventricular mass and central arterial elasticity in the adult spontaneously hypertensive rat (SHR) and in a subgroup of SHR in which blood pressure was normalized by chronic antihypertensive drug treatment; results were compared with those of age-matched normotensive Wistar-Kyoto rats. Two indexes of arterial elasticity, based on the measurement of aortic pressure pulse wave velocity, were used. First, the slope relating carotidofemoral pulse wave velocity to blood pressure in the phenylephrine-infused pithed preparation was used as a pressure-independent index of wall elasticity. Second, to account for hypertension- and treatment-induced aortic remodeling, elastic modulus was determined from the pulse wave velocity recorded when blood pressure reached that measured in awake animals before anesthesia and pithing, together with values for wall thickness and lumen diameter evaluated by histomorphometric analysis after in situ fixation at the same pressure. In control SHR, regression analysis of variance revealed significant correlations between left ventricular mass and both wave velocity/pressure slope and elastic modulus. Chronic antihypertensive treatment normalized all three parameters. In conclusion, this new technique provides experimental evidence of a link between left ventricular mass and central arterial elasticity.

Aortic stiffness and left ventricular mass in a rat model of isolated systolic hypertension

We tested whether cardiac mass can be related to decreased aortic stiffness in an original rat model of isolated systolic hypertension. Increased aortic stiffness was produced by calcium overload of elastic arteries after vitamin D3 plus nicotine treatment. Half of the animals were chronically treated with the angiotensin-converting enzyme inhibitor perindopril (1 mg/kg per day PO). Rats were pithed, and lower body vascular resistance was measured. Blood pressure was then increased by phenylephrine infusion, and carotidofemoral pulse wave velocity was measured. This value together with those for thoracic aorta internal diameter and medial thickness (determined after in situ fixation and histomorphometry) were used to calculate elastic modulus. Vitamin D3 plus nicotine treatment produced parallel increases in cardiac mass and elastic modulus, with a significant correlation between the two. There was no significant change in resistance. Treatment with perindopril reversed the changes in cardiac mass and elastic modulus but had no effect on resistance after calcium overload of the elastic arteries. In this model of isolated systolic hypertension, we showed that cardiac mass is related to arterial elasticity.

Effect of chronic ANG I-converting enzyme inhibition on aging processes. IV. Cerebral blood flow regulation

Age-related changes in systemic arterial blood pressure, basal cerebral blood flow (CBF), and CBF regulatory capacity were investigated in awake 6-, 12-, 24-, and 30-mo-old male Wistar (WAG/Rij) rats, one-half of which received the angiotensin I-converting enzyme inhibitor (ACEI) perindopril from 6 mo onward. There was no age-dependent change in mean arterial blood pressure, basal CBF, or cerebrovascular reactivity to hypercapnia, but the lower limit of CBF autoregulation rose from 70 mmHg at 6 and 12 mo to 90 mmHg in 24- and 30-mo-old animals. ACEI lowered mean arterial blood pressure but had no effect on basal CBF or on cerebrovascular reactivity to hypercapnia. ACEI shifted the lower limit of CBF autoregulation to a 20-mmHg-lower level in 12- and 24-mo animals but not in rats treated for 2 yr, i.e., from the ages of 6 to 30 mo. In conclusion, the main age-related change in CBF regulation was an increase in the lower limit of CBF autoregulation to a higher blood pressure level. Treatment with ACEI partially restored the lower limit of CBF autoregulation.

Increased arterial distensibility induced by the angiotensin-converting enzyme inhibitor, lisinopril, in normotensive rats

1. We investigated possible structural correlates of the beneficial effect of chronic angiotensin-converting enzyme inhibition (ACEI) with lisinopril on the aortic distensibility of normotensive rats. 2. Experiments were performed in young (4-month old), normotensive, Wistar rats which received lisinopril in their drinking water (0.9 or 9 mg kg-1 day-1) for 9 months. 3. Following ACEI treatment, rats were pithed and aortic pulse wave velocity was measured during the progressive rise in mean arterial blood pressure produced by i.v. infusion of the alpha 1-adrenoceptor agonist, phenylephrine. The slope of the regression line relating aortic pulse wave velocity to mean arterial blood pressure was taken as an index of aortic distensibility. Following this, the aorta was fixed in situ at a normotensive pressure level and histomorphometry was performed. We also measured the calcium content of the aortic wall by atomic absorption. 4. The lower dose of lisinopril failed to lower systolic arterial blood pressure (unanaesthetized rat) or mean arterial blood pressure (pithed rat). Chronic ACEI with the higher dose of lisinopril lowered both systolic arterial blood pressure (104 +/- 6 mmHg, controls 133 +/- 4 mmHg, unanaesthetized), and mean arterial blood pressure (27 +/- 1 mmHg, controls 34 +/- 2 mmHg, pithed). 5. Although the lower dose of lisinopril did not lower blood pressure, it did improve aortic distensibility as revealed by a fall in the slope relating aortic pulse wave velocity (Y) to mean arterial blood pressure (X). Values were 5.7 +/- 0.7, 3.8 +/- 0.6 and 2.7 +/- 0.3 in controls, and in low and high ACEI groups, respectively. 6. Lisinopril treatment did not modify the calcium content, the internal and external diameters or the medial thickness of the aorta. Chronic ACEI did, however, increase the thickness of the medial elastic fibres (controls 3.55 +/- 0.05 microm, low dose ACEI 4.05 +/- 0.15 gm (P<0.05), and high dose ACEI4.18 +/- 0.15 microm (P<0.05)).7. In conclusion, we would suggest that ACEI treatment with a low dose of lisinopril can decrease aortic stiffness via a pressure-independent mechanism which possibly involves an effect of ACEI on elastic fibres.

Haemodynamic effects of a new dihydropyridine calcium entry blocker, S-12968-(-), in a rat model of cardiovascular calcium overload

1. The haemodynamic effects of S-12968-(-), a new dihydropyridine calcium entry blocker (enantiomer of S-11568), were compared with those of the stereoisomer, S-12967-(+), nifedipine, and sodium nitroprusside. 2. A first experiment was performed in conscious, young male rats chronically implanted with femoral artery and vein cannula and repeated in rats previously treated with vitamin D3 and nicotine. Such treatment produces marked vascular calcium overload, especially of the compliance arteries, with no overt sign of toxicity as far as can be judged from the plasma profile. 3. In conscious rats the hypotensive effects of S-12968-(-), nifedipine and sodium nitroprusside were of similar potency. The falls in blood pressure produced by nifedipine and sodium nitroprusside were accompanied by reflex tachycardia which was less marked in the vascular calcium overload model. S-12968-(-) did not induce reflex tachycardia. S-12967-(+) increased blood pressure in both models. 4. A second experiment was performed in open-chest pentobarbitone-anaesthetized rats with electromagnetic flowprobes on the ascending aorta. In controls the falls in blood pressure produced by low doses (0.1 and 0.3 mg kg-1, i.v.) of S-12968-(-) were accompanied by falls in total peripheral resistance. The higher dose (1 mg kg-1, i.v.) of S-12968-(-) produced no change in total peripheral resistance, and in rats pretreated with vitamin D3 and nicotine, cardiac output fell. 5. In conclusion, S-12968-(-) appears to have a dual action and to lower blood pressure at higher doses at least in part by a cardiac effect. This phenomenon is more pronounced in rats pretreated with vitamin D3 and nicotine.6. S-12967-(+) resembles a calcium channel activator in this model.