Anesthesia for transcatheter aortic valve implantation

Impact of Aortic Valve Stenosis on Coronary Hemodynamics and the Instantaneous Effect of Transcatheter Aortic Valve Implantation

BACKGROUND

Aortic valve stenosis (AS) induces compensatory alterations in left ventricular hemodynamics, leading to physiological and pathological alterations in coronary hemodynamics. Relief of AS by transcatheter aortic valve implantation (TAVI) decreases ventricular afterload and is expected to improve microvascular function immediately. We evaluated the effect of AS on coronary hemodynamics and the immediate effect of TAVI.

METHODS AND RESULTS

Intracoronary pressure and flow velocity were simultaneously assessed at rest and at maximal hyperemia in an unobstructed coronary artery in 27 patients with AS before and immediately after TAVI and in 28 patients without AS. Baseline flow velocity was higher and baseline microvascular resistance was lower in patients with AS as compared with controls, which remained unaltered post-TAVI. In patients with AS, hyperemic flow velocity was significantly lower as compared with controls (44.5±14.5 versus 54.3±18.6 cm/s; P=0.04). Hyperemic microvascular resistance (expressed in mm Hg·cm·s(-1)) was 2.10±0.69 in patients with AS as compared with 1.80±0.60 in controls (P=0.096). Coronary flow velocity reserve in patients with AS was lower, 1.9±0.5 versus 2.7±0.7 in controls (P<0.001). Improvement in coronary hemodynamics after TAVI was most pronounced in patients without post-TAVI aortic regurgitation. In these patients (n=20), hyperemic flow velocity increased significantly from 46.24±15.47 pre-TAVI to 56.56±17.44 cm/s post-TAVI (P=0.003). Hyperemic microvascular resistance decreased from 2.03±0.71 to 1.66±0.45 (P=0.050). Coronary flow velocity reserve increased significantly from 1.9±0.4 to 2.2±0.6 (P=0.009).

CONCLUSIONS

The vasodilatory reserve capacity of the coronary circulation is reduced in AS. TAVI induces an immediate decrease in hyperemic microvascular resistance and a concomitant increase in hyperemic flow velocity, resulting in immediate improvement in coronary vasodilatory reserve.

Comparison of sedation and general anaesthesia for transcatheter aortic valve implantation on cerebral oxygen saturation and neurocognitive outcome†

BACKGROUND

Transcatheter aortic valve implantation (TAVI) is a treatment strategy for patients with severe aortic stenosis. Although general anaesthesia (TAVI-GA) and sedation (TAVI-S) have previously been described for TAVI, the difference in safety and efficacy of both methods has not been studied in a randomized trial.

METHODS

The INSERT trial was a single centre, controlled parallel-group trial with balanced randomization. Sixty-six patients (68-94 yr) with acquired aortic stenosis undergoing transfemoral CoreValve™ were assigned to TAVI-GA or TAVI-S. Comparable operative risk was determined from risk-scores (EUROscore, STS-Score). Monitoring and anaesthetic drugs were standardized. Near-Infrared-Spectroscopy was used to monitor cerebral-oxymetry blinded. Primary outcome was the perioperative cumulative cerebral desaturation. As secondary outcomes, changes in neurocognitive function and respiratory and haemodynamic adverse events were evaluated.

RESULTS

Of 66 included patients, 62 (TAVI-GA: n=31, TAVI-S: n=31) were finally analysed. Baseline characteristics were comparable. In 24 patients (39%) cerebral desaturation was observed. Cumulative cerebral desaturation was comparable (TAVI-GA:(median [IQR]) (0[0/1308] s%) vs. TAVI-S:(0[0/276] s%); P=0.505) between the groups. Neurocognitive function did not change within and between groups. Adverse events were more frequently observed in TAVI-S patients (P<0.001). Bradypnoea (n=16, 52%) and the need for airway manoeuvres (n=11, 36%) or bag-mask-ventilation (n=6, 19%) were the most common respiratory adverse events.

CONCLUSIONS

Cerebral desaturation occurred in both patient groups, but there was no significant difference between the two groups. Based on primary outcome, both methods were shown to be comparable. Neurocognitive outcome was similar. The higher incidence of adverse events in the sedation group suggests a potential advantage of general anaesthesia.

CLINICAL TRIAL REGISTRATION

NCT 01251328.

Transcatheter Aortic Valve Implantation: First Applications and Short Term Outcomes in Our Clinic

OBJECTIVE

The objective of this study is to evaluate the first applications and short term outcomes of transcatheter aortic valve implantation (TAVI) in our clinic, which is a new technology for the patients with high risk for surgical aortic valve replacement (SAVR).

MATERIALS AND METHODS

Between January 2010 and December 2012, twenty five patients (16 males, 9 females; mean age 74.04±8.86 years) diagnosed with severe aortic stenosis, who were at high risk for surgery (EuroSCORE II: 5.58±4.20) and underwent TAVI in our clinic, were evaluated. The demographic and clinical characteristics of patients, anaesthetic management, complications during pre- and post-operative periods and the mortality rate in the first 30 days and six months were recorded.

RESULTS

Edwards SAPIEN Valve prostheses were implanted by transfemoral approach (percutaneously in 10 patients and surgically in 15 patients) in all patients. The TAVI procedure was performed under general anaesthesia. The success rate of the TAVI procedure was 100%. Three patients had limited dissection of the femoral artery; however, intervention was not needed due to good distal perfusion rate. Permanent pacemaker was implanted to four patients because of long-term atrioventricular blockage. After the procedure, all patients were transferred to the Intensive Care Unit (ICU) and all patients were extubated in the ICU. The mean mechanical ventilation duration (minutes) was 166.20±39.32, the mean critical care unit stay (day) was 5.64±2.99 and the mean hospital stay (day) was 11.92±5.54. Acute renal failure was observed in one patient and stroke was observed in two patients on the first postoperative day. The mortality rate in the first 30 days and 6 months was found to be 4% and 16%, respectively.

CONCLUSION

Transcatheter aortic valve implantation is a great option for patients with severe aortic stenosis who are at high risk for SAVR. In our institute, procedural success and short term outcomes for patients underwent TAVI were found to be similar to the other studies in the national and international literature.

Salvaging catastrophe in transcatheter aortic valve implantation: rehearsal, preassigned roles, and emergency preparedness

PURPOSE

Emergency rescue plans for acute complications during transcatheter aortic valve implantation (TAVI) commonly include cardiopulmonary resuscitation, femoro-femoral cardiopulmonary bypass (CPB), and hemodynamic stabilization before definitive intervention is achieved. Nevertheless, most cases of emergency resuscitation remain chaotic and disorganized and often take longer than necessary, even in experienced centres. We sought to determine which factors and procedures may be associated with improved patient outcomes when emergencies arise during TAVI.

SOURCES

MEDLINE(®) and EMBASE™ were searched with the following key words: "TAVI" or "TAVR" or "transcatheter valve implantation" or "transcatheter valve replacement" and "emergency cardiac surgery" or "conversion". Two hundred seventeen articles met the criteria and were reviewed.

PRINCIPAL FINDINGS

Utilization of a formal emergency checklist by a multidisciplinary TAVI team may reduce procedural errors, smooth the transition to CPB, and ultimately speed the delivery of corrective measures including emergency cardiac surgery.

CONCLUSION

A well-organized regularly-rehearsed emergency rescue plan that preassigns resuscitative roles may shorten the duration of patient instability and resuscitation and improve patient outcomes when catastrophe occurs in TAVI. The anesthesia team plays a central role in preventing, detecting, and treating intraprocedural complications during TAVI.

Direct Aortic Transcatheter Aortic Valve Implantation: Anaesthesia Attentions

Surgical replacement of aortic valve is the gold standard therapy for severe aortic valve stenosis. Transcatheter Aortic Valve Implantation (TAVI) is less invasive and becomes an alternative therapy reserved for patients with high operative risk. TAVI can be performed via transfemoral, transapical or transaortic approach. Patients with diseased or difficult femoral/iliac vascular access, poor left ventricular function and significant respiratory disease are not suitable for transfemoral or transapical approach. In this scenario, direct transaortic approach of TAVI is a feasible option. This case report presents a case of a 76-year-old man with symptomatic severe aortic valve stenosis who underwent general anaesthesia and was successfully treated by direct transaortic TAVI using Edwards Sapien XT aortic bioprosthesis.

Predictors of Prolonged Hemodynamic Compromise After Valve Deployment During Transcatheter Aortic Valve Implantation

OBJECTIVE

To identify the risk factors of prolonged hemodynamic compromise caused by rapid pacing for valve deployment during transcatheter aortic valve implantation.

DESIGN

A retrospective study.

SETTING

Academic hospital.

PARTICIPANTS

Forty-seven patients with severe aortic stenosis who underwent transcatheter aortic valve implantation.

INTERVENTIONS

The time after the end of rapid pacing until systolic arterial pressure and SvO2 recovery (systolic arterial pressure>90 mmHg and SvO2>65%) was defined as "the hemodynamic recovery time" and was measured from online anesthetic charts. The total study population was divided into 2 groups according to the recovery time (third quartile in all patients; 33 and 14 patients in the early and delayed recovery groups, respectively). Subsequently, the factors associated with prolonged hemodynamic compromise after rapid pacing for valve deployment were identified by univariate and multivariate analyses.

MEASUREMENTS AND MAIN RESULTS

Multivariate analysis identified left ventricular end-diastolic diameter (odds ratio, 0.774; 95% confidence interval, 0.608-0.915) and SvO2 (odds ratio, 0.748; 95% confidence interval, 0.590-0.868) as independent factors associated with prolonged hemodynamic compromise after rapid pacing for valve deployment.

CONCLUSIONS

SvO2 and left ventricular end-diastolic diameter were found to be significant independent predictors of prolonged hemodynamic compromise immediately after rapid pacing for valve deployment during transcatheter aortic valve implantation.