Propranolol monotherapy in angiosarcoma - A window-of-opportunity study (PropAngio)

BACKGROUND

Angiosarcoma is a rare and aggressive cancer of the endothelial cells. Propranolol, a non-selective β-blocker, was able to initiate apoptosis in angiosarcoma cell lines and its anti-tumor activity has been described in several case reports. The aim of this trial was to prospectively evaluate the anti-tumor activity of propranolol monotherapy in patients with angiosarcoma before proceeding to standard of care treatment.

METHODS

Propranolol was dosed 80 mg to 240 mg/day for 3 to 6 weeks according to a dose titration schedule. The primary endpoint was clinical response (response according to RECIST 1.1 or stable disease with improvement of cutaneous lesions) in at least three patients. Exploratory objectives included histologic response (>30% decrease in Ki-67), FDG PET response, and β-receptor expression levels.

RESULTS

Fourteen patients were enrolled. The median duration of treatment was 26 days (range 21-42 days). The median highest propranolol dose was 160 mg/day (range 80 - 240 mg). Two patients showed clinical response (14%, 95% CI 3-100%). One of these patients showed a partial metabolic response on PET-CT. None of the tumors showed histologic response. The most common adverse event was grade 1/2 bradycardia (86%). There were no grade ≥ 3 adverse events. ADRB2 was overexpressed in 16 out of 18 tumors, in both responders and non-responders. None of the tumors showed ADRB1 overexpression.

CONCLUSIONS

This window-of-opportunity trial did not show clinical efficacy of propranolol monotherapy. However, two out of 14 patients did show clinical benefit. ADRB1/2 expression did not correlate with clinical response.

Can the hemodynamic model in heart failure be restored based on analysis of ventricular-arterial coupling?

The hemodynamic model was inappropriate to explain the disappointing effect of vasodilation and the beneficial effect of beta-blockade in chronic heart failure. A more nuanced hemodynamic analysis, taking both steady and pulsatile hemodynamics into consideration, improves insight into these apparently enigmatic effects. Of particular interest is the velocity of early systolic flow as a determinant of left ventricular afterload. Several drugs, in particular beta-blockers, directly or indirectly, influence the velocity of early systolic flow. Thus, the hemodynamic model in heart failure may deserve reconsideration.

Limited Effect of Beta-blockade on Postoperative Outcome After Laparoscopic Gastric Bypass Surgery

BACKGROUND

The benefit of beta-blockade on postoperative outcome remains controversial, though recent studies have suggested a role during major non-cardiac surgery. The benefit of beta-blockade during minimally invasive gastric bypass surgery remains unclear. The aim of the present study was to evaluate the possible association between preoperative beta-blocker therapy and postoperative outcome after laparoscopic gastric bypass surgery.

METHODS

Patients operated with primary laparoscopic gastric bypass surgery in Sweden between 2007 and 2017 were identified through the Scandinavian Obesity Surgery Registry. The dataset was linked to the Swedish National Patient Registry, the Swedish Prescribed Drug Registry, and Statistics Sweden. The main outcome was serious postoperative complication within 30 days of surgery; with postoperative complication, 90-day and 1-year mortality, and weight loss at 2 years after surgery as secondary endpoints. The Poisson regression model was used to evaluate primary and secondary categorical outcomes. A general mixed model was performed to evaluate 2-year weight loss.

RESULTS

In all, 50281 patients were included in the study. No difference was seen between patients on beta-blockade and the control group regarding postoperative complications (adjusted incidence rate ratio 1.04 (95%CI 0.93-1.15), p = 0.506), serious postoperative complication (adjusted IRR 1.06 95%CI 0.89-1.27), p = 0.515), 90-day mortality (adjusted IRR 0.71 (95%CI 0.24-2.10), p = 0.537), and 1-year mortality (adjusted IRR 1.26 (95%CI 0.67-2.36), p = 0.467). Weight loss 2 years after surgery was slightly greater in patients on beta-blockade (adjusted coefficient 0.53 (95%CI 0.19-0.87), p = 0.002).

CONCLUSIONS

Beta-blockade has limited impact on postoperative outcome after laparoscopic gastric bypass surgery.

Effects of sympatho-vagal interaction on ventricular electrophysiology and their modulation during beta-blockade

AIMS

The effects of sympatho-vagal interaction on heart rate (HR) changes are characterized by vagal dominance resulting in accentuated antagonism. Complex autonomic modulation of ventricular electrophysiology may exert prognostic arrhythmic impact. We examined the effects of concurrent sympathetic (SNS) and vagus (VNS) nerve stimulation on ventricular fibrillation threshold (VFT) and standard restitution (RT) in an isolated rabbit heart preparation with intact dual autonomic innervation, with and without beta-blockade.

METHODS AND RESULTS

Monophasic action potentials were recorded from left ventricular epicardial surface of dual-innervated isolated heart preparations from New Zealand white rabbits (n = 18). HR, VFT and RT were measured during different stimulation protocols (Protocol 1: VNS-SNS; Protocol 2: SNS-VNS) involving low- and high-frequency stimulations. A sub-study of Protocol 2 was performed in the presence of metoprolol tartrate. In both protocols, HR changes were characterized by vagal-dominant bradycardic component, affirming accentuated antagonism. During concurrent high-frequency VNS (HV), SNS prevails in lowering VFT in a frequency-sensitive manner during low (LS) or high (HS)-frequency stimulations (HV-LS: -2.8 ± 0.8 mA; HV-HS: -4.0 ± 0.9 mA, p < .05 vs. HV), with accompanying steepening of relative RT slope gradients (HV-LS: 223.54 ± 37.41%; HV-HS: 295.20 ± 60.86%, p < .05 vs. HV). In protocol 2, low (LV) and high (HV) vagal stimulations during concurrent HS raised VFT (HS-LV: 1.0 ± 0.4 mA; HS-HV: 3.0 ± 0.6 mA, p < .05 vs HS) with associated flattening of RT slopes (HS-LV: 32.40 ± 4.97%;HS-HV: 38.07 ± 6.37%; p < .05 vs HS). Metoprolol abolished accentuated antagonism in HR changes, reduced VFT and flattened RT globally during SNS-VNS.

CONCLUSIONS

Accentuated antagonism is absent in ventricular electrophysiological changes during sympatho-vagal interaction with sympathetic effect prevailing, suggesting a different mechanism at the ventricular level from heart rate effects. Metoprolol nullified accentuated antagonism with additional anti-fibrillatory effect beyond adrenergic blockade during sympatho-vagal stimulations.

A case of congenital long QT syndrome, type 8, undergoing laparoscopic hysterectomy with general anesthesia

OBJECTIVE

Patients with Long QT syndrome (LQTS) P may present with torsades de pointes, ventricular tachycardia (VT), or ventricular fibrillation (VF) and are at risk of sudden cardiac death.

MATERIALS AND METHODS

A 38 y/o female patient with uterus myoma developed VF during laparoscopic assisted vaginal hysterectomy surgery. Defibrillation was delivered and the electrocardiogram (ECG) returned to sinus rhythm after CPR.

RESULTS

Patient survived and implantable cardioverter-defibrillator was implanted and received beta-blocker therapy. ECG obtained in out-patient clinic still showed QT interval prolongation, but revealed no prolongation few months after persistent beta-blocker therapy. LQTS type 8 (CACNA1C E768del mutation) was identified by genetic DNA sequencing study.

CONCLUSIONS

Patients with concealed LQTS may have normal QT interval unless exposing to stress or specific stimuli. Unexpected ventricular arrhythmia may happen during any medical management. We should avoid triggers of QT prolongation, and get familiar with management of the episode.

Treatment strategies for the right heart in pulmonary hypertension

The function of the right ventricle (RV) determines the prognosis of patients with pulmonary hypertension. While much progress has been made in the treatment of pulmonary hypertension, therapies for the RV are less well established. In this review of treatment strategies for the RV, first we focus on ways to reduce wall stress since this is the main determinant of changes to the ventricle. Secondly, we discuss treatment strategies targeting the detrimental consequences of increased RV wall stress. To reduce wall stress, afterload reduction is the essential. Additionally, preload to the ventricle can be reduced by diuretics, by atrial septostomy, and potentially by mechanical ventricular support. Secondary to ventricular wall stress, left-to-right asynchrony, altered myocardial energy metabolism, and neurohumoral activation will occur. These may be targeted by optimising RV contraction with pacing, by iron supplement, by angiogenesis and improving mitochondrial function, and by neurohumoral modulation, respectively. We conclude that several treatment strategies for the right heart are available; however, evidence is still limited and further research is needed before clinical application can be recommended.

Does early beta-blockade in isolated severe traumatic brain injury reduce the risk of post traumatic depression?

INTRODUCTION

Depressive symptoms occur in approximately half of trauma patients, negatively impacting on functional outcome and quality of life following severe head injury. Pontine noradrenaline has been shown to increase upon trauma and associated β-adrenergic receptor activation appears to consolidate memory formation of traumatic events. Blocking adrenergic activity reduces physiological stress responses during recall of traumatic memories and impairs memory, implying a potential therapeutic role of β-blockers. This study examines the effect of pre-admission β-blockade on post-traumatic depression.

METHODS

All adult trauma patients (≥18 years) with severe, isolated traumatic brain injury (intracranial Abbreviated Injury Scale score (AIS) ≥3 and extracranial AIS <3) were recruited from the trauma registry of an urban university hospital between 2007 and 2011. Exclusion criteria were in-hospital deaths and prescription of antidepressants up to one year prior to admission. Pre- and post-admission β-blocker and antidepressant therapy data was requested from the national drugs registry. Post-traumatic depression was defined as the prescription of antidepressants within one year of trauma. Patients with and without pre-admission β-blockers were matched 1:1 by age, gender, Glasgow Coma Scale, Injury Severity Score and head AIS. Analysis was carried out using McNemar's and Student's t-test for categorical and continuous data, respectively.

RESULTS

A total of 545 patients met the study criteria. Of these, 15% (n=80) were prescribed β-blockers. After propensity matching, 80 matched pairs were analyzed. 33% (n=26) of non β-blocked patients developed post-traumatic depression, compared to only 18% (n=14) in the β-blocked group (p=0.04). There were no significant differences in ICU (mean days: 5.8 (SD 10.5) vs. 5.6 (SD 7.2), p=0.85) or hospital length of stay (mean days: 21 (SD 21) vs. 21 (SD 20), p=0.94) between cohorts.

CONCLUSION

β-blockade appears to act prophylactically and significantly reduces the risk of post-traumatic depression in patients suffering from isolated severe traumatic brain injuries. Further prospective randomized studies are warranted to validate this finding.

Retrieval-induced forgetting under psychosocial stress: no reduction by delayed stress and beta-adrenergic blockade

Retrieval-induced forgetting (RIF) is the phenomenon that 'retrieval-practice', the repeated retrieval of a subset of initially learned material, can impair the recall of episodically related memories. Previous studies showed that RIF is eliminated when retrieval-practice is carried out under psycho-social stress, anxiety, or in negative mood. However, pharmacological manipulation by hydrocortisone did not eliminate the effect. This study investigated the effect of beta-adrenergic blockade on stress-induced modulations of RIF, addressing possible interactive effects of the glucocorticoid and sympatho-adrenomedullary systems. Participants learned categorized word lists and then received either 60 mg propranolol or a placebo. After 90 min they were exposed to the TSST. A third group did not receive any medication and performed a non-stressful control task with the same timing as the other two groups. Finally, all participants underwent retrieval-practice and final recall. Both TSST groups exhibited a stress-induced increase in cortisol-levels, and the placebo group also exhibited large increases in markers of sympathetic nervous system activity and more psychological distress at the time of retrieval-practice. Although, overall recall was poorer under stress, an overall RIF effect emerged irrespective of group and showed no clear modulation by stress with or without beta-adrenergic blockade. In previous demonstrations of RIF elimination by negative emotion, state induction and retrieval-practice followed very briefly after initial learning. Given that both the previous study of hydrocortisone effects on RIF and the present study used longer delays between learning and retrieval-practice, the possibility that stress effects on retrieval-practice eliminate RIF only relatively briefly after learning is discussed.

Autonomic nerve activity and blood pressure in ambulatory dogs

BACKGROUND

The relationship between cardiac autonomic nerve activity and blood pressure (BP) changes in ambulatory dogs is unclear.

OBJECTIVE

The purpose of this study was to test the hypotheses that simultaneous termination of stellate ganglion nerve activity (SGNA) and vagal nerve activity (VNA) predisposes to spontaneous orthostatic hypotension and that specific β₂-adrenoceptor blockade prevents the hypotensive episodes.

METHODS

We used a radiotransmitter to record SGNA, VNA, and BP in eight ambulatory dogs. Video imaging was used to document postural changes.

RESULTS

Of these eight dogs, five showed simultaneous sympathovagal discharges in which the minute-by-minute integrated SGNA correlated with integrated VNA in a linear pattern (group 1). In these dogs, abrupt termination of simultaneous SGNA-VNA at the time of postural changes (as documented by video imaging) was followed by abrupt (>20 mm Hg over four beats) drops in BP. Dogs without simultaneous on/off firing (group 2) did not have drastic drops in pressure. ICI-118,551 (ICI, a specific β₂-blocker) infused at 3 µg/kg/h for 7 days significantly increased BP from 126 mm Hg (95% confidence interval 118-133) to 133 mm Hg (95% confidence interval 125-141; P = .0001). The duration of hypotension (mean systolic BP <100 mm Hg) during baseline accounted for 7.1% of the recording. The percentage was reduced by ICI to 1.3% (P = .01).

CONCLUSION

Abrupt simultaneous termination of SGNA-VNA was observed at the time of orthostatic hypotension in ambulatory dogs. Selective β₂-adrenoceptor blockade increased BP and reduced the duration of hypotension in this model.