A highly penetrant ACTA2 mutation of thoracic aortic disease

BACKGROUND

The role of ACTA2 mutations in Familial Aortic Disease has been increasingly recognized. We describe a highly penetrant variant (R118Q) in a family with aortic disease.

CASE REPORT

A patient presented to us for elective repair of an ascending aortic aneurysm with a family history of his mother expiring after aortic dissection. Genetic testing revealed he was a heterozygous carrier of the ACTA2 missense mutation R118Q. Subsequently, all living family members were tested for this variant and a full medical history was obtained to compile a family tree for the variant and penetrance of an aortic event (defined as lifetime occurrence of aortic surgery / dissection). In total 9 family members were identified and underwent genetic testing with 7/9 showing presence of the ACTA2 R118Q mutation or an aortic event. All patients over the age of 50 (n = 4) had an aortic event. Those events occurred at ages 54, 55, 60, and 62 (mean event at 57.8 ± 3.9 years). Three family members with the variant under the age of 40 have not had an aortic event and most are undergoing regular aortic surveillance via CT scan.

CONCLUSIONS

Existing studies of known ACTA2 mutations describe a 76% aortic event rate by 85 years old. The R118Q missense mutation is a less common ACTA2 variant, estimated to be found in about 5% of patients with known mutations. Prior studies have predicted the R118Q mutation to have a slightly decreased risk of aortic events compared to other ACTA2 mutations. In this family, however, we demonstrate 100% penetrance of aortic disease above age 50. In today's era of excellent outcomes in elective aortic surgery, our team aggressively offers elective repair. We advocate for strict aortic surveillance for patients with this variant and would consider elective aortic replacement at 4.5 cm, or at an even smaller diameter in patients with a strong family history of dissection who are identified with this mutation.

Location of Superior Vena Cava Tears in Transvenous Lead Extraction

BACKGROUND

Superior vena cava (SVC) tears are rare but potentially lethal complications associated with transvenous lead extraction. When lacerations occur, surgeons need to be prepared for an emergent response. Nonetheless, little is known about the precise whereabouts of these lesions. Understanding the location and injury patterns enables a more anticipated and targeted surgical response.

METHODS

We collected data via physician interviews after an SVC laceration occurred. These physicians were identified through the US Food and Drug Administration's Manufacturer and User Facility Device Experience database and independent physician reports of adverse events. We identified 116 reports of SVC tears between July 1, 2016, and July 31, 2018. For an SVC tear to be included in our registry, a cardiothoracic surgeon had to be physically present to confirm the injury via emergent sternotomy. In each case, the surgeon recorded the SVC injury's exact location after a repair was attempted.

RESULTS

During the study period, 116 SVC tears were confirmed by sternotomy. Tears occurred in any combination of the following locations: SVC-innominate vein, body of the SVC, and SVC-right atrial junction. The majority of tears (n = 72; 62%) were located in the isolated body of the SVC, followed by the SVC-right atrial junction (n = 23;19.8%) and the SVC-innominate junction (n = 17;14.6%). Combined tears were rare, accounting for only 3.6% (n = 4) of the adverse events recorded.

CONCLUSIONS

Most SVC tears occurred in the isolated body of the SVC. The second most common location was the SVC-right atrial junction. The SVC-innominate junction was the third most common location for these injuries. Combined tears were uncommon.

Review of cerebral perfusion strategies for aortic surgery with application for minimally invasive approaches

Aortic arch and hemiarch surgery necessitate the temporary interruption of blood perfusion to the brain. Despite its complexity, hemiarch and ascending aortic surgery can be performed via a minimally invasive approach. Due to the higher risk of neurological injury during a circulatory arrest, several techniques were developed to further protect the brain during this surgery. We searched the Embase, Medline, and Cochrane databases and identified articles reporting outcomes of antegrade and retrograde cerebral perfusion strategies. Herein, we outline surgical approaches, intra-operative technical considerations, and clinical outcomes of hemiarch and ascending aortic surgery. Hemiarch and ascending aortic surgery is associated with a higher risk of mortality and morbidity. Attention to the optimal approach and cerebral protection strategy has been shown to significantly affect outcomes and mitigate risk.

Endovascular Occlusion Balloon for Treatment of Superior Vena Cava Tears During Transvenous Lead Extraction

Background:

Superior vena cava (SVC) tears are one of the most lethal complications in transvenous lead extraction. An endovascular balloon can occlude the SVC in the event of a laceration, preventing blood loss and offering a more controlled surgical field for repair. An early study demonstrated that proper use of this device is associated with reduced mortality. Thereafter, high-volume extractors at the Eleventh Annual Lead Management Symposium developed a best practice protocol for the endovascular balloon.

Methods:

We collected data on adverse events in lead extraction from July 1, 2016, to July 31, 2018. Data were prospectively collected from both a US Food and Drug Administration–maintained database and physician reports of adverse events as they occurred. We gathered case details directly from extracting physicians. Confirmed SVC tears were analyzed for patient demographics, case details, and index hospitalization mortality.

Results:

From July 1, 2016, to July 31, 2018, 116 confirmed SVC events were identified, of which 44.0% involved proper balloon use and 56.0% involved no use or improper use. When an endovascular balloon was properly used, 45 of 51 patients (88.2%) survived in comparison to 37 of 65 patients (56.9%) when a balloon was not used or improperly used ( P =0.0002). Furthermore, multivariate regression modeling found that proper balloon deployment was an independent, negative predictor of in-hospital mortality for patients who experienced an SVC laceration (odds ratio, 0.13; 95% CI, 0.04–0.40; P <0.001).

Conclusions:

From July 1, 2016, through July 31, 2018, patients undergoing lead extraction were more likely to survive SVC tears when treatment included an endovascular balloon.

Minimally Invasive Techniques to Avoid Sternotomy in Complex Lead Extraction Cases

Cardiac device lead extractions have increased in frequency over the past several years. Although most of these procedures are successfully performed through a percutaneous approach, certain cases may be unmanageable using conventional methods. The traditional approach for such complex cases has been median sternotomy. However, four surgical techniques offer a less-invasive alternative. These include the transatrial approach, the subxiphoid approach, the left minithoracotomy/thoracoscopy, and the ministernotomy. In the present study, we reviewed data from patients who underwent minimally invasive, surgical lead extraction at our institution from January 2003 to October 2017 using an ongoing, prospective registry. Summary statistics were generated for age, sex, device extracted, lead dwell time (years), procedure indication, major/minor complications and procedural success as defined by the 2017 Heart Rhythm Society consensus statement, and survival at discharge. Between January 2003 and October 2017, 14 cases at our center were managed via a transatrial approach, whereas 11 involved the subxiphoid approach, 19 involved a left minithoracotomy or thoracoscopy, and one involved a ministernotomy. For the transatrial approach, all cases were classified as procedural successes and all patients were discharged alive. Additionally, for the subxiphoid approach, all cases were deemed procedural successes, whereas survival at discharge was 90.9%. For the left minithoracotomy/thoracoscopy, all cases were procedural successes and survival at discharge was 94.7%. Lastly, the ministernotomy was successfully used to remove an infected, retained lead fragment from the innominate vein. In conclusion, at our institution, the transatrial approach, the subxiphoid approach, the left minithoracotomy/thoracoscopy, and the ministernotomy were used as minimally invasive, surgical approaches that represent fairly safe and effective alternatives to median sternotomy in complex cases unamenable to management via conventional, percutaneous approaches to lead extraction.

A Systematic Review and Meta-analysis of Ventilator-associated Pneumonia in Adults in Asia: An Analysis of National Income Level on Incidence and Etiology

Background

Ventilator-associated pneumonia (VAP) is the commonest hospital-acquired infection (HAI) in intensive care. In Asia, VAP is increasingly caused by resistant gram-negative organisms. Despite the global antimicrobial resistance crisis, the epidemiology of VAP is poorly documented in Asia.

Methods

We systematically reviewed literature published on Ovid Medline, Embase Classic, and Embase from 1 January 1990 to 17 August 2017 to estimate incidence, prevalence, and etiology of VAP. We performed a meta-analysis to give pooled rates and rates by country income level.

Results

Pooled incidence density of VAP was high in lower- and upper-middle-income countries and lower in high-income countries (18.5, 15.2, and 9.0 per 1000 ventilator-days, respectively). Acinetobacter baumannii (n = 3687 [26%]) and Pseudomonas aeruginosa (n = 3176 [22%]) were leading causes of VAP; Staphylococcus aureus caused 14% (n = 1999). Carbapenem resistance was common (57.1%).

Conclusions

VAP remains a common cause of HAI, especially in low- and middle-income countries, and antibiotic resistance is high.

Surgical and Hybrid Lead Extraction

Surgical and hybrid lead extraction has developed considerably over the past several decades. Although transvenous lead extraction is the standard approach to remove infected or malfunctioning cardiac implantable electronic device leads, surgical approaches may be necessary in complex cases not amenable to transvenous lead extraction or in cases that involve concomitant pathologies, such as tricuspid valve regurgitation. We describe our experience with 4 minimally invasive surgical approaches to lead extraction as well as our experience with hybrid open heart surgery and transvenous lead extraction as an option for patients who present with concomitant conditions.

Coil embolization to successfully treat annular rupture during transcatheter aortic valve replacement

Aortic annular rupture is one of the most feared complications of transcatheter aortic valve replacement (TAVR). This complication often presents as sudden cardiac tamponade with hypotension and requires urgent intervention. The traditional rescue strategy for such cases is emergency surgical intervention, yet the mortality remains high considering most patients who undergo TAVR are not candidates for open heart surgery. As such, there is a need for percutaneous alternatives to treat this critical complication. Here, we describe a case of annular rupture during TAVR that was successfully treated with coil embolization at the rupture site. This case illustrates the use of coil embolization as a treatment strategy in patients with acute aortic annular rupture who are at high-risk for surgical intervention.

Pearls of Wisdom for High-Risk Laser Lead Extractions: A Focused Review

Due to new indications and improved technology, the incidence of laser lead extraction (LLE) has significantly increased over the past years. While LLE has been well studied and proven to be safe and effective, only few studies are geared toward the anesthesiologist's role during high-risk LLEs. This article utilized both a focused review and authors' experience to investigate anesthetic protocols during LLEs. Through this review, we recommend best practices for the anesthesiologist including appropriate procedure location, onsite availability of a cardiac surgeon, availability of a cardiopulmonary bypass machine, and intraoperative use of echocardiography to detect and address potential complications during high-risk LLEs.

Long-term outcomes of prophylactic placement of an endovascular balloon in the vena cava for high-risk transvenous lead extractions

BACKGROUND

Many clinicians use the strategy of prophylactically placing an endovascular balloon before transvenous lead extraction, yet there are no data regarding this practice.

OBJECTIVE

This study assesses long-term outcomes of prophylactic placement of an endovascular balloon in the venae cavae of patients during transvenous lead extraction.

METHODS

From April 1, 2016 to March 31, 2017 data were prospectively collected at 2 international cardiovascular centers on patients who had the balloon prophylactically placed in the venae cavae. Patients were monitored for a minimum of 3 months to capture any associated adverse events.

RESULTS

Twenty-one patients had the balloon prophylactically placed in the venae cavae during lead extraction. Sixteen patients were male (76%); the mean age was 57.6 ± 18.7 years; and the mean body mass index was 26.1 ± 4.4 kg/m². The mean lead dwell time was 11.2 ± 8.3 years, with an average of 2.2 ± 1.1 leads per case, and most indications for extraction were noninfectious (62%). Two minor complications (10%, pocket hematomas) and 1 major complication (5%, cardiac tamponade) occurred during the procedure. All cases (100%) were procedural successes, and all patients (100%) were discharged alive. On follow-up (6.8 ± 3.7 months), all patients were alive and reported no adverse events related to prophylactic balloon placement, such as pulmonary emboli or deep venous thrombi.

CONCLUSION

During the study period, we observed no acute or long-term adverse outcomes associated with prophylactic placement of an endovascular balloon in the venae cavae of patients undergoing transvenous lead extraction.