Efficacy and safety of adenosine, rapid ventricular pacing and hypothermia in cerebral aneurysms clipping: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: Cerebral aneurysms in complex anatomical locations and intraoperative rupture can be challenging. Many methods to reduce blood flow can facilitate its exclusion from the circulation. This study evaluated the safety and efficacy of using adenosine, rapid ventricular pacing, and hypothermia in cerebral aneurysm clipping. METHODS: Databases (PubMed, Embase, and Web of Science) were systematically searched for studies documenting the use of adenosine, rapid ventricular pacing, and hypothermia in cerebral aneurysm clipping and were included in this single-arm meta-analysis. The primary outcome was 30-day mortality. Secondary outcomes included neurological outcomes by mRs and GOS, and cardiac outcomes. We evaluated the risk of bias using ROBIN-I, a tool developed by the Cochrane Collaboration. OpenMetaAnalyst version 2.0 was used for statistical analysis and I2 measured data heterogeneity. Heterogeneity was defined as an I2 > 50%. RESULTS: Our systematic search yielded 10,100 results. After the removal of duplicates and exclusion by title and abstract, 64 studies were considered for full review, of which 29 were included. The overall risk of bias was moderate. The pooled proportions of the adenosine analysis for the different outcomes were: For the primary outcome: 11,9%; for perioperative arrhythmia: 0,19%; for postoperative arrhythmia: 0,56%; for myocardial infarction incidence: 0,01%; for follow-up good recovery (mRs 0-2): 88%; and for neurological deficit:14.1%. In the rapid ventricular pacing analysis, incidences were as follows: peri operative arrhythmia: 0,64%; postoperative arrhythmia: 0,3%; myocardial infarction: 0%. In the hypothermia analysis, the pooled proportion of 30-day mortality was 11,6%. The incidence of post-op neurological deficits was 35,4% and good recovery under neurological analysis by GOS was present in 69.2%. CONCLUSION: The use of the three methods is safe and the related complications were very low. Further studies are necessary, especially with comparative analysis, for extended knowledge.

Unstable ventricular tachycardia requiring defibrillation from rapid ventricular pacing during basilar apex aneurysm clipping.

BACKGROUND: Controlled hypotension is an important tool in the open treatment of complex intracranial aneurysms. Of the available methodologies, rapid ventricular pacing (RVP) provides titratable, sustained hypotension with a relatively safe profile. METHOD: We report the case of a 63-year-old woman who underwent a combined subfrontal and subtemporal approach for clipping of anterior communicating artery and basilar apex aneurysms. RVP was used during initial dissection of the basilar apex aneurysm and perforators but caused uncontrolled ventricular tachycardia requiring synchronized defibrillation. After restoration of hemodynamic stability, the aneurysm was uneventfully clipped. CONCLUSION: Preparation for unstable cardiac arrhythmias is needed with RVP.

Rapid ventricular pacing during transcatheter valve procedures using an internal device and programmer: A demonstration of feasibility.

OBJECTIVES: To develop a protocol for using a pre-existing, permanent pacemaker or defibrillator device for rapid ventricular pacing during transcatheter valve procedures and demonstrate feasibility. BACKGROUND: Placement of a passive fixation, temporary pacemaker wire is considered routine during most transcatheter valve procedures to facilitate controlled or rapid ventricular pacing at the time of balloon expansion or valve deployment. Many patients presenting for such procedures have a pre-existing, permanent pacemaker or defibrillator device which could be used for the same function, obviating the need for temporary pacemaker wire placement. METHODS: We developed a strategy for rapid pacing from the pre-existing device using a programmer during transcatheter valve procedures in consecutive patients over a 3-month period. Complications and clinical outcomes were recorded. RESULTS: There were 135 transcatheter valve procedures performed during the study. Of these, 28 (20.7%) had pre-existing devices (17 transcatheter aortic valve replacement, 3 aortic valve-in-valve, 2 mitral valve-in-valve, and 6 balloon aortic valvuloplasty). All patients underwent rapid ventricular pacing using a commercially available device programmer. There were no adverse events related to device pacing and no patients required placement of a temporary pacemaker wire during the procedure. At 30-days follow-up, there were no deaths, one major vascular complication related to arterial access, and one patient with renal failure requiring dialysis. CONCLUSION: Pacing from a commercially available device programmer is safe, feasible, and may reduce both procedural cost and complications such as cardiac tamponade by avoiding placement of a temporary pacemaker lead during transcatheter valve procedures.

What are the options for cardiac standstill during aneurysm surgery? A systematic review.

To perform a systematic review of the techniques for transient circulatory arrest during intracerebral aneurysm surgery according to the PRISMA guidelines. Search of PubMed and Google Scholar using the following: ("heart arrest" OR "cardiac standstill"[All Fields]) AND ("intracranial aneurysm" OR "intracranial"[All Fields] AND "aneurysm"[All Fields]). A total of 41 original articles were retrieved, of which 17 were excluded (review articles, editorials and single-case reports). A total of 24 separate articles published between 1984 and 2018 were included in the final analysis, where the majority of patients harbored anterior circulation giant or large aneurysms. Adenosine-induced cardiac arrest gave a short, temporary asystole. The method had benefits in aneurysm with a broad neck, a thin wall, in specific localizations with narrow surgical corridors or in case of intraoperative rupture. Rapid ventricular pacing (RVP) allows a longer and more easily controlled hypotension. Its use is largely limited to elective cases. Deep hypothermic circulatory arrest required a complex infrastructure, and fatal procedure complications lead to a 11.5-30% 30-day mortality rate, limiting its application to giant or complex aneurysm of the basilar artery or to residual posterior circulation aneurysm after endovascular treatment. Adenosine and RVP are both effective options to facilitate clipping of complex aneurysms. However, their use in patient with ischemic heart disease and cardiac arrhythmias should be avoided, and their safety in the context of subarachnoid hemorrhage is yet to be determined. Today, deep hypothermic circulatory arrest is almost obsolete due to endovascular alternatives.

Transvenous embolization of thalamic arteriovenous malformation under transient cardiac standstill.

Transvenous embolization (TE) has been increasingly applied for arteriovenous malformation (AVM) treatment. Transient cardiac standstill (TCS) has been described in cerebrovascular surgery but is uncommon for endovascular embolization. The authors present a patient with a ruptured thalamic AVM in whom both techniques were applied simultaneously. Surgery was considered, but the patient refused. Transarterial embolization was performed with an incomplete result. The deep-seated draining vein provided sole access to the AVM. A microcatheter was advanced into the draining vein. Under TCS, achieved with rapid ventricular pacing, complete AVM embolization was obtained. One-year magnetic resonance imaging and cerebral angiography demonstrated no residual AVM.The video can be found here: https://youtu.be/CAzb9md_xBU.

Randomized comparison of balloon aortic valvuloplasty performed with or without rapid cardiac pacing: The pacing versus no pacing (PNP) study.

OBJECTIVES: To compare the effectiveness and safety of balloon aortic valvuloplasty (BAV) performed with or without rapid ventricular pacing (RP). BACKGROUND: BAV technique is poorly standardized. METHODS: One hundred consecutive patients were randomly assigned 1:1 between BAV performed with or without RP. Exclusion criteria were an immediate indication for surgical or transcatheter aortic valve replacement, presentation in cardiogenic shock or pulmonary edema refractory to medical stabilization. RESULTS: There were 51 patients in the BAV group performed with RP, 49 in the BAV group without RP (noRP). Procedural success (50% hemodynamic gradient reduction) was achieved in 37.3% and 55.1%, respectively (P = 0.16). Fewer people in the noRP group complained of poor tolerance to the procedure (16% vs 41%). The primary efficacy endpoint, a 50% reduction in the mean echocardiographic trans-aortic gradient, was met in 21/49 patients in the noRP group compared to 20/51 in the RP (42.9% vs 39.2%; P = 0.84). No significant difference between the groups was observed in the primary safety endpoint, a 30-day composite of death, myocardial infarction, stroke, acute aortic regurgitation, and BARC bleeding ≥3 (8.2% noRP vs 13.7%; P = 0.53). The noRP group required fewer bailout temporary pacemakers (P = 0.048) and had a lower incidence of moderate/severe renal function worsening (4.1% vs 17.6%; P = 0.052). CONCLUSIONS: Rapid ventricular pacing did not influence BAV efficacy or safety and tolerance was slightly worse.

A longer total duration of rapid ventricular pacing does not increase the risk of postprocedural myocardial injury in patients who undergo transcatheter aortic valve implantation.

Rapid ventricular pacing (RVP) is used during transcatheter aortic valve implantation (TAVI). RVP disturbs myocardial oxygen balance, and when prolonged, it may cause procedure-related myocardial injury (PMI). This study investigated whether a longer duration of RVP increased the occurrence of PMI or worsened long-term mortality after TAVI. We retrospectively analyzed data from 188 patients who underwent TAVI in our institute from January 2013 to July 2015. Myocardial injury was represented by the peak value of creatine kinase-myocardial band (CK-MB) within 72 h after the procedure; an increase greater than 5 times the upper reference limit was regarded as PMI. There was no difference in RVP time (RVPT) between patients with and without PMI (median [range]: 57 [9-189] s vs. 54 [0-159] s, p = 0.9). A higher peak CK-MB was significantly correlated with the apical approach for the procedure (p < 0.001) but not with total RVPT (p = 0.22). A subanalysis of 133 patients whose troponin I was tested within 72 h postprocedurally showed no correlation between the peak value and RVPT (p = 0.40). Shortening RVPT did not result in myocardial protection; thus, RVPT during TAVI should be sufficient to optimize valve placement.

Influence of continuously evolving transcatheter aortic valve implantation technology on cerebral oxygenation.

This study assessed the influence of the evolution in Transcatheter Aortic Valve Implantation technology on cerebral oxygenation. Cerebral oxygenation was measured continuously with Near-Infrared Spectroscopy and compared retrospectively between balloon-expandable, self-expandable and differential deployment valves which were implanted in 12 (34%), 17 (49%) and 6 patients (17%), respectively. Left and right SctO2 values were averaged at four time points and used for analysis (i.e. at baseline, balloon-aortic valvuloplasty, valve deployment, and at the end of the procedure). During balloon-aortic valvuloplasty and valve deployment, cerebral oxygenation decreased in patients treated with balloon or self-expandable valves (balloon-expandable: p = 0.003 and p = 0.002; self-expandable: p < 0.001 and p = 0.003, respectively). The incidence of cerebral desaturations below 80% of baseline was significantly larger in patients treated with balloon-expandable valves (p = 0.001). In contrast, patients who received differential deployment valves never experienced a cerebral desaturation below 80% of baseline. Furthermore, both the incidence and duration below a cerebral oxygenation of 55% was significantly different between balloon and self-expandable valves (p = 0.038 and p = 0.018, respectively). This study demonstrated that Transcatheter Aortic Valve Implantation procedures are associated with significant cerebral desaturations, especially during balloon-aortic valvuloplasty and valve deployment. Moreover, our results showed that latest innovations in Transcatheter Aortic Valve Implantation technology beneficially influenced the adequacy of cerebral perfusion.

Changes in cerebral oxygen saturation during transcatheter aortic valve replacement.

Cerebral oxygen saturation (rSO2) is a non-invasive monitor used to monitor cerebral oxygen balance and perfusion. Decreases in rSO2 >20 % from baseline have been associated with cerebral ischemia and increased perioperative morbidity. During transcatheter aortic valve replacement (TAVR), hemodynamic manipulation with ventricular pacing up to 180 beats per minute is necessary for valve deployment. The magnitude and duration of rSO2 change during this manipulation is unclear. In this small case series, changes in rSO2 in patients undergoing TAVR are investigated. Ten ASA IV patients undergoing TAVR with general anesthesia at a university hospital were prospectively observed. Cerebral oximetry values were analyzed at four points: pre-procedure (baseline), after tracheal intubation, during valve deployment, and at procedure end. Baseline rSO2 values were 54.5 ± 6.9 %. After induction of general anesthesia, rSO2 increased to a mean of 66.0 ± 6.7 %. During valve deployment, the mean rSO2 decreased <20 % below baseline to 48.5 ± 13.4 %. In two patients, rSO2 decreased >20 % of baseline. Cerebral oxygenation returned to post-induction values in all patients 13 ± 10 min after valve deployment. At procedure end, the mean rSO2 was 67.6 ± 8.1 %. As expected, rapid ventricular pacing resulting in the desired decrease in cardiac output during valve deployment was associated with a significant decrease in rSO2 compared to post-induction values. However, despite increased post-induction values in all patients, whether related to increased inspired oxygen fraction or reduced cerebral oxygen consumption under anesthesia, two patients experienced a significant decrease in rSO2 compared to baseline. Recovery to baseline was not immediate, and took up to 20 min in three patients. Furthermore, baseline rSO2 in this population was at the lower limit of the published normal range. Significant cerebral desaturation during valve deployment may potentially be limited by maximizing rSO2 after anesthetic induction. Future studies should attempt to correlate recovery in rSO2 with recovery of hemodynamics and cardiac function, provide detailed neurological assessments pre and post procedure, determine the most effective method of maximizing rSO2 prior to hemodynamic manipulation, and provide the most rapid method of recovery of rSO2 following valve deployment.

Rapid Ventricular Pacing Facilitates Transarterial Embolization in Vein of Galen Malformations.

Background: Mural type vein of Galen malformation (mVOGM) is a congenital high flow arteriovenous shunt between choroidal arteries and the prosencephalic vein of Markowski leading to heart failure and hydrovenous disorder in children. Embolizing fistulous connections can be challenging and typically requires adjunctive techniques such as induced hypotension, balloon-assisted flow control, and creation of a coil basket. These maneuvers add time, complexity, and unpredictability. Rapid ventricular pacing (RVP) has been proposed as an alternative strategy with fewer drawbacks, but has not been well studied. The approach involves catheterizing the right ventricle with a pacing catheter connected to a temporary external pacemaker. Prior to embolization, RVP is initiated to lower cardiac output. Following embolization, pacing is discontinued, and the heart returns to sinus rhythm. Methods: We performed RVP in five mVOGM patients from 4/2020 through 7/2021. Accounting for multiple procedures, RVP was utilized in ten cases and twenty-six pedicles. Results: Ventricular capture was achieved in all instances and was well tolerated, without arrhythmia. Casting the arterial pedicle with liquid embolic immediately adjacent to, or traversing, the fistulous point was achieved in 9/10 cases. There were no procedural complications. In 1 case, creation of a coil basket in the venous pouch was required to achieve a stable arterial cast Conclusions: This report describes the largest case series utilizing RVP in mVOGM. The technique appears safe and well tolerated.

Thoracic endovascular aortic repair of an anastomosis pseudoaneurysm after the Bentall procedure assisted by rapid ventricular pacing: A case report.

Background: Although commonly used for the treatment of descending aortic dissection, endovascular repair is challenging for ascending aortic pseudoaneurysms. Rapid ventricular pacing (RVP), a method that temporarily impedes cardiac output by stopping ventricular activity, heralds potential benefits for thoracic endovascular aortic repair (TEVAR) during precision landing. Recently, we successfully treated an anastomosis pseudoaneurysm after the Bentall procedure using TEVAR assisted by RVP. Case report: A 69-year-old male was admitted to our hospital with a ascending aortic anastomosis pseudoaneurysm. He had undergone a Bentall procedure and a coronary artery bypass grafting nine years prior. After extensive consultation, the decision was made to perform TEVAR with the assistance of RVP. After a covered stent graft was delivered to the precise location of the ascending aorta, RVP was performed at a frequency of 180 beats/min with a pacemaker. When a flattened arterial blood wave of <50 mmHg was observed, the stent graft was released precisely between the opening of the coronary graft and innominate artery. Angiography revealed the presence of an endoleak; therefore, a set of interlock coils were packed into the aneurysm. Subsequent angiography showed intact blood flow in the aorta, superior arch branches, and coronary graft vessels. The patient recovered uneventfully after the procedure. He was discharged six days later and was doing well at the eight-month follow-up. Conclusion: The case indicates that TEVAR assisted by RVP is a promising combination for ascending aortic pseudoaneurysm in selected patients.

Rapid ventricular overdrive pacing and other advanced flow-control techniques for the endovascular embolization of vein of galen malformations.

Endovascular embolization is the primary strategy in the management for vein of Galen malformations (VOGM). However, despite significant advances in endovascular embolization technologies and techniques, VOGMs remain very technically challenging lesions largely due to the high-flow arteriovenous shunts present in these malformations. A variety of advanced flow-control techniques can be implemented to mitigate the risk of venous escape and increase the safety and efficacy of endovascular treatment. These techniques include regionally targeted strategies (transvenous embolization and balloon-assisted transarterial embolization) and global flow-control methods (pharmacologic cardiac arrest and rapid ventricular overdrive pacing). Each of these strategies are associated with unique advantages and disadvantages, highlighting the importance of a patient-specific approach when treating these challenging lesions.

Transvenous Embolization Technique for Brain Arteriovenous Malformations.

Transvenous embolization is potentially curative for small AVMs with favorable anatomic features, such as inaccessible arterial feeders, deep location, and/or a single draining vein. Successful embolization requires the control of arterial blood flow and successful navigation of the draining vein. This allows permeation of the embolizate into the nidus. Arterial inflow may be controlled using a hypercompliant balloon or systemic hypotension. We have described the use of transvenous rapid ventricular pacing and adenosine to achieve transient controlled hypotension. This requires a multidisciplinary approach, yet provides high chances of complete obliteration of the AVM.

Rapid Ventricular Pacing as a Safe Procedure for Clipping of Complex Ruptured and Unruptured Intracranial Aneurysms.

Surgical treatment of intracranial aneurysm requires advanced technologies to achieve optimal results. Recently, rapid ventricular pacing (RVP) has been described to be an elegant technique that facilitates clip reconstruction of complex unruptured intracranial aneurysm (uIA). However, there is also a growing need for intraoperative tools to ensure safe clip reconstruction of complex ruptured intracranial aneurysm (rIA). We conducted a retrospective analysis of 17 patients who underwent RVP during surgical reconstruction of complex aneurysms. Nine patients had uIA while eight patients underwent surgery for rIA suffering from consecutive subarachnoid hemorrhage (SAH). Hemodynamic data, critical events, laboratory results, and anesthesia-related complications were evaluated. No complications were reported concerning anesthesia induction and induction times were similar between patients exhibiting uIA or rIA (p = 0.08). RVP induced a significant decline of median arterial pressure (MAP) in both groups (p < 0.0001). However, median MAP before and after RVP was not different in both groups (uIA group: p = 0.27; rIA group: p = 0.18). Furthermore, high-sensitive Troponin T (hsTnT) levels were not increased after RVP in any group. One patient in the rIA group exhibited ventricular fibrillation and required cardiopulmonary resuscitation, but has presented with cardiac arrest due to SAH. Otherwise, no arrhythmias or complications occurred. In summary, our data suggest RVP to be feasible in surgery for ruptured intracranial aneurysms.

Thrombectomy and Clip Occlusion of a Giant, Stent-Coiled Basilar Bifurcation Aneurysm: 3-Dimensional Operative Video.

Giant basilar apex aneurysms are associated with significant therapeutic challenges.1-6 Multiple techniques exist to treat giant basilar apex aneurysms, including direct clipping, stent-assisted coil embolization, and proximal occlusion with bypass revascularization.7-9 Hypothermic circulatory arrest was a useful adjunct for surgical repair of these aneurysms but has been abandoned because of associated risks.10,11 Rapid ventricular pacing can achieve similar aneurysm softening with minimal risks and assist in clip occlusion. This case illustrates clip occlusion of a giant, partially thrombosed, previously stent-coiled basilar apex aneurysm in a 15-yr-old boy with progressive cranial neuropathies and sensorimotor impairment. Although a wire was placed preoperatively for ventricular pacing, it was not needed during the procedure. Patient consent was obtained. A right-sided orbitozygomatic craniotomy transcavernous approach with anterior and posterior clinoidectomies was performed. The basilar quadrification was dissected, and proximal control was obtained. After aneurysm trapping, the aneurysm was incised and thrombectomized using an ultrasonic aspirator. Back-bleeding from the aneurysm was anticipated, and ventricular pacing was ready, but back-bleeding was minimal. With the coil mass left in place, stacked, fenestrated clips were applied in a tandem fashion to occlude the aneurysm neck. Indocyanine green videoangiography confirmed occlusion of the aneurysm and patency of parent and branch arteries. The patient was at a neurological baseline after the operation, with improvement in motor skills and cognition at 3-mo follow-up. This case demonstrates the use of trans-sylvian-transcavernous exposure, rapid ventricular pacing, and thrombectomy amid previous coils and stents to clip a giant, thrombotic basilar apex aneurysm. Used with permission from Barrow Neurological Institute, Phoenix, Arizona.

First-in-Man 4-Chamber Pressure-Volume Analysis During Transcatheter Aortic Valve Replacement for Bicuspid Aortic Valve Disease.

This report constitutes a first-in-man description of pressure-volume analysis in all 4 cardiac chambers before and after transcatheter aortic valve replacement. Pressure-volume analysis demonstrated that the hemodynamic consequences of valve replacement are chamber-specific and influenced by all aspects of the procedure (i.e., rapid ventricular pacing), not just valve deployment. (Level of Difficulty: Advanced.).

Clinical impact of rapid ventricular pacing on the left atrial posterior wall isolation by a cryoballoon application: a randomized controlled trial.

PURPOSE: Rapid ventricular pacing (RVP) was reported to improve the cooling effects of the cryoballoon (CB). The aim of this study was to investigate the safety and efficacy of RVP for left atrial posterior wall isolation (PWI) by the CB. METHODS: One hundred consecutive patients (males 80, mean age 63 ± 10 years) with persistent atrial fibrillation underwent left atrial roof (LA-RB) and bottom block line (LA-BB) creation by CB to achieve PWI. Patients were randomized into two groups according to whether they underwent PWI with (RVP group, n = 50) or without RVP (control group, n = 50). RESULTS: The nadir CB temperature (NCT) during the LA-RB and LA-BB creation was significantly lower in the RVP group than control group (LA-RB - 45.7 °C and - 43.9 °C, p < 0.001, and LA-BB - 42.4 °C and - 40.0 °C, p < 0.001). The success rate of the LA-RB creation was significantly higher in the RVP group than the control group (98% vs. 88%, p = 0.039), however, there were no significant differences regarding the LA-BB creation (66% vs. 52%, p = 0.15) and PWI (66% vs. 50%, p = 0.1) between the two groups. The PWI success rate did not differ whether CB freezing was prematurely terminated due to an excessive luminal esophageal temperature (LET) drop in the RVP group (65.8% vs. 66.7%, respectively, p = 0.96). CONCLUSIONS: RVP significantly decreased the NCT during the CB application resulting in the significant improvement of success rate of the LA-RB. The advantage of RVP in terms of the accomplishing PWI was not affected even when the CB freezing was prematurely terminated due to an excessive LET drop.

Rapid Ventricular Pacing for Neurovascular Surgery: A Study on Cardiac and Cerebral Effects.

BACKGROUND AND OBJECTIVE: Intraoperative rupture of a cerebral aneurysm during neurosurgery can be a devastating event that increases perioperative morbidity and mortality. Rapid ventricular pacing (RVP) is a technique to obtain flow arrest for short periods of time during dissection or rupture of the aneurysm. The objective of this study was to evaluate the neurological and cardiac effects of repetitive periods of RVP during cerebrovascular surgery. METHODS: Data from patients who underwent repetitive RVP during craniotomy for cerebrovascular disorders were retrospectively analyzed from a single-center medical records database (Cegeka Medical Health Care Systems). We compared preoperative and postoperative troponin levels (cTnI) to assess cardiac ischemia. Preoperative and postoperative magnetic resonance imaging (MRI) results were screened for RVP-induced infarcts by evaluating diffusion restriction in the hemisphere contralateral to the operated side and the fossa posterior. RESULTS: A total of 37 patients were analyzed. An immediate decrease of systolic arterial blood pressure (<60 mm Hg) was achieved after initiation of RVP. Postoperative MRI did not reveal areas of diffusion restriction. RVP tended to be a predictor of postoperative cTnI increase. Preoperative and postoperative cTnI levels were higher in patients with a subarachnoid hemorrhage compared to patients without one. After 24 hours cTnI jevels normalized to preoperative values. CONCLUSIONS: Systolic arterial blood pressure decreased after RVP but normalized immediately when pacing stopped. MRI of the brain did not show RVP-related ischemia and the limited cTnI level increase normalized to preoperative values. Therefore, RVP during short periods of time seems to be a safe blood pressure-lowering technique for the brain and heart.