Graft flow assessment and early coronary artery bypass graft failure: a computed tomography analysis

OBJECTIVES

We evaluated graft patency by computed tomography and explored the determinants of intraoperative mean graft flow (MGF) and its contribution to predict early graft occlusion.

METHODS

One hundred and forty-eight patients under a single surgeon were prospectively enrolled. Arterial and endoscopically harvested venous conduits were used. Intraoperative graft characteristics and flows were collected. Graft patency was blindly evaluated by a follow-up computed tomography at 11.4 weeks (median).

RESULTS

Graft occlusion rate was 5.2% (n = 22 of 422; 8% venous and 3% arterial). Thirteen were performed on non-significant proximal stenosis while 9 on occluded or >70% stenosed arteries. Arterial and venous graft MGF were lower in females (Parterial = 0.010, Pvenous = 0.009), with median differences of 10 and 13.5 ml/min, respectively. Arterial and venous MGF were associated positively with target vessel diameter ≥1.75 mm (Parterial = 0.025; Pvenous = 0.002) and negatively with pulsatility index (Parterial < 0.001; Pvenous < 0.001). MGF was an independent predictor of graft occlusion, adjusting for EuroSCORE-II, pulsatility index, graft size and graft type (arterial/venous). An MGF cut-off of 26.5 ml/min for arterial (sensitivity 83.3%, specificity 80%) and 36.5 ml/min for venous grafts (sensitivity 75%, specificity 62%) performed well in predicting early graft occlusion.

CONCLUSIONS

We demonstrate that MGF absolute values are influenced by coronary size, gender and graft type. Intraoperative MGF of >26.5 ml/min for arterial and >36.5 ml/min for venous grafts is the most reliable independent predictor of early graft patency. Modern-era coronary artery bypass graft is associated with low early graft failure rates when transit time flow measurement is used to provide effective intraoperative quality assurance.

Type A aortic syndromes in COVID-19 positive patients: Case series from a UK multicentre study

OBJECTIVE

The coronavirus disease (COVID-19) increases the respiratory complications and carries a higher mortality in the immediate postoperative period. The aim of this study was to analyze the outcomes of patients with type A acute aortic syndromes (AAS) diagnosed with COVID-19 in the perioperative period.

METHODS

Retrospective analysis of prospectively collected data between March and August 2020 from 20 participating cardiac surgery centers in the United Kingdom.

RESULTS

Among 122 patients who underwent emergency surgical repair for type A AAS at the participating centers, 3 patients (2.5%) tested positive for COVID-19 in the preoperative screeing, and 4 cases turned to be positive in the postoperative period having been operated on an unknown COVID-19 status. Another patient was diagnosed of COVID-19 disease based on radiological features. These eight patients had increased postoperative complications, including respiratory failure, longer ventilation times, and Intensive Therapy Unit (ITU) stay and increased mortality when compared with COVID-19 negative patients.

CONCLUSION

COVID-19 disease in the perioperative period of type A AAS poses a challenge. Despite the increasing morbidity and mortality associated with the virus, the prognosis of the aortic disease is poorer and emergency surgery should not be contraindicated based on the COVID-19 diagnosis alone.

Complete resection of pulmonary artery hemangioma on the beating heart

Cardiac hemangiomas are rare entities and very few cases have been reported where they originate from the main arteries of the heart. We present a case of hemangioma arising from the main pulmonary artery, which was completely resected with clear margins on the beating heart.

Early experience of aortic surgery during the COVID-19 pandemic in the UK: A multicentre study

BACKGROUND

A significant restructuring of the healthcare services has taken place since the declaration of the coronavirus disease 2019 (COVID-19) pandemic, with elective surgery put on hold to concentrate intensive care resources to treat COVID-19 as well as to protect patients who are waiting for relatively low risk surgery from exposure to potentially infected hospital environment.

METHODS

Multicentre study, with 19 participating centers, to define the impact of the pandemic on the provision of aortovascular services and patients' outcomes after having adapted the thresholds for intervention to guarantee access to treatment for emergency and urgent conditions. Retrospective analysis of prospectively collected data, including all patients with aortovascular conditions admitted for surgical or conservative treatment from the 1st March to the 20th May 2020.

RESULTS

A total of 189 patients were analyzed, and 182 underwent surgery. Diagnosis included: aneurysm (45%), acute aortic syndrome (44%), pseudoaneurysm (4%), aortic valve endocarditis (4%), and other (3%). Timing for surgery was: emergency (40%), urgent (34%), or elective (26%). In-hospital mortality was 12%. Thirteen patients were diagnosed with COVID-19 during the peri-operative period, and this subgroup was not associated with a higher mortality.

CONCLUSIONS

There was a significant change in service provision for aortovascular patients in the UK. Although the emergency and urgent surgical activity were maintained, elective treatment was minimal during early months of the pandemic. The preoperative COVID-19 screening protocol, combined with self-isolation and shielding, contributed to the low incidence of COVID-19 in our series and a mortality similar to that of pre-pandemic outcomes.

Left ventricular rupture postradiofrequency catheter ablation: Transaortic, intraventricular patch exclusion repair

Left ventricular (LV) rupture after radiofrequency catheter ablation (RFCA) is a rare but life-threatening complication. We describe a case of LV rupture secondary to RFCA successfully treated with a transaortic, intraventricular patch exclusion surgical repair, assisted by transoesophageal echocardiography and epicardial ultrasound assessment. Patch exclusion technique can offer a physiological repair with better preservation of myocardial mechanical characteristics and possibly less damage to healthy myocardium and surrounding structures.

The fate of patients with acute aortic syndrome during the coronavirus disease 2019 (COVID-19) pandemic: A UK multicenter study

Objective

The coronavirus disease 2019 (COVID-19) pandemic has posed challenges to health care services across the world. There has been a significant restructuring of health care resources to protect services for patients with COVID-19–related illness and to maintain emergency and urgent medical and surgical activity. This study assessed access to emergency treatment, logistical challenges, and outcomes of patients with acute aortic syndrome during the early months of the COVID-19 pandemic in the United Kingdom.

Methods

This was a multicenter study, from March 1 to May 20, 2020 that included 19 cardiac centers, was a retrospective analysis of prospectively collected data obtained from individual centers' national cardiac surgical databases. Demographic details, choice of treatment, operative details, and outcomes were collected. COVID-19 screening, timing of surgery, and outcomes of COVID-19–positive and –negative patients were also analyzed.

Results

In total, 88 patients presented with acute aortic syndrome to participating centers from March 1 to May 20, 2020. There were 79 aortic dissections (89.8%), 7 intramural hematomas (7.9%), and 2 penetrating aortic ulcers (2.3%). Seventy-nine patients (89.8%) underwent surgery. In-hospital mortality was 25.3% (n = 20). Postoperative complications included 13.9% postoperative stroke (11.4% permanent and 2.3% temporary), 16.5% rate of hemofiltration, and 10.1% rate of tracheostomy. Nine patients were treated conservatively with a mortality of 60%. Seven patients were diagnosed with COVID-19, and there was no associated mortality.

Conclusions

Despite extensive restructuring of health care resources, access to emergency and urgent treatment for patients with acute aortic syndrome was maintained in the early months of the COVID-19 pandemic in the United Kingdom. Clinical outcomes were similar to the prepandemic period.

Beyond patency: Functional assessment of adequacy using internal mammary artery grafting to the left anterior descending artery

INTRODUCTION

Arterial graft physiology influences the long-term outcome of coronary artery bypass grafting (CABG). We studied factors that can affect the overall resistance to flow using internal mammary artery grafting to the left anterior descending artery.

METHODS

This was a prospective, nonrandomized observational study of 100 consecutive patients who underwent elective on-pump isolated or combined valve surgery and CABG. Coronary stenoses were assessed using conventional and quantitative coronary angiography assessment. The flow and pulsatility index (PI) of the grafts were assessed by transit-time flowmetry during cardioplegic arrest and at the end of the operation. Fractional polynomials were used to explore linearity, followed by multivariable regression analysis.

RESULTS

Univariate analysis demonstrated higher flows at the end of the operation in patients who had higher flows with the cross-clamp on (P < .001), in males (P = .004), in patients with a low PI at the end of the operation (P = .04), and in patients with a larger size of the recipient artery (P = .005). Multivariable regression analysis showed that the graft flow at the end of the operation was significantly associated with the mean flow with the cross-clamp on (P < .001), sex (P = .003), and PI at the end of the operation (P = .003). Concomitant valve surgery did not influence flows. Male patients had 18 mL/min higher flow.

CONCLUSIONS

The graft flow at the end of the operation can be determined by the flow with the cross-clamp on, the PI with the cross-clamp off and coronary artery. We reported differences in the graft flows between sexes, and for first the time, we introduced the concepts of "adequate flow" and "resistance-to-forward-flow" for patent coronary grafts.

Thrombotic Thrombocytopenic Purpura Following Aortic Valve Replacement with St. Jude Medical Trifecta Bio-Prosthesis

Thrombocytopenia is a recognized complication following aortic valve replacement (AVR). While post-operative thrombotic thrombocytopenic purpura (TTP) is less common than heparin-induced thrombocytopenia (HIT), it is associated with high mortality and morbidity and prompt diagnosis and treatment is vital. In this case report, we describe the first reported case of TTP after AVR using the trifecta bio-prosthesis. We recommend that patients with severe and progressive thrombocytopenia following biological AVR should have early screening for both HIT and TTP, to shorten the decision-making process and provide the appropriate therapy.

Coronary artery surgery in octogenarians: evolving strategies for the improvement in early and late results

The purpose of this study was to investigate retrospectively early and late outcomes of coronary artery bypass grafting (CABG) in a large series of octogenarians. We retrospectively reviewed the data of 241 octogenarian patients who underwent CABG between April 2002 and April 2009 at our institution. Mean age was 84.7 ± 1.8 years. Patients affected by concomitant coexistent organic aortic, mitral, or tricuspid valve disease were excluded from the study. Patients with functional secondary ischemic mitral incompetence were included in the study. The majority of the patients were male. Angina pectoris functional class III/IV accounted for 164 patients (68%). Left ventricular ejection fraction ≤35% was diagnosed in 38 patients (15.8%). Early mortality rate was 5.8% (14 patients). Causes of death were cardiac related in 10 patients. Preoperative independent predictors of in-hospital mortality obtained with multivariate analysis were extracardiac arteriopathy, New York Heart Association class III/IV, and previous percutaneous transluminal coronary angioplasty (PTCA). The overall mean follow-up was 41.6 ± 25.9 months (range 1-87.6 months). Among the 222 contacted survivors, there were 16 (7.2%) deaths during the follow-up. The actuarial survival was 91.9% at 1 year and 83.5% at 5 years. On multivariate analysis, time to late death was adversely affected by preoperative extracardiac arteriopathy and previous PTCA. Advanced age alone should not be a deterrent for CABG if it has been determined that the benefits outweigh the potential risk. A careful selection of optimal candidates, based on the evaluation of their systemic comorbidities, appears mandatory in order to obtain the greatest benefit for these high-risk patients.