Coronary artery bypass grafting in acute coronary syndromes: modern indications and approaches

PURPOSE OF REVIEW

Acute coronary syndromes (ACS) are a leading cause of morbidity and mortality worldwide, with approximately 1.2 million hospitalizations annually in the U.S. This review aims to explore the contemporary evidence regarding revascularization strategies, including percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG), in ACS patients. It also addresses the unresolved questions concerning the optimal procedural aspects of surgery and antithrombotic therapy for secondary prevention postsurgery.

RECENT FINDINGS

Recent studies highlight that while PCI is generally preferred for its timeliness in high-risk non-ST-elevation ACS (NSTE-ACS) patients, CABG offers a benefit in terms of cardiovascular events in those with multivessel disease, particularly in the presence of diabetes and higher coronary disease complexity. For ST-elevation myocardial infarction (STEMI), CABG is less frequently utilized due to the preference for primary PCI, but it remains crucial for patients with complex anatomy or failed PCI. Furthermore, the optimal timing and type of antiplatelet therapy post-CABG remain controversial, with current evidence supporting the use of dual antiplatelet therapy (DAPT) to reduce ischemic events but necessitating careful management to balance bleeding risks.

SUMMARY

In patients with ACS, the choice between PCI and CABG depends on the complexity of coronary disease and patient comorbidities. CABG is particularly beneficial for multivessel disease in NSTE-ACS and specific STEMI cases where PCI is not feasible. The management of antiplatelet therapy postsurgery requires a nuanced approach to minimize bleeding risks while preventing thrombotic complications. Further randomized clinical trials are needed to solidify these findings and guide clinical practice.

Outcomes of mitral valve transcatheter edge-to-edge repair for patients with hemodynamic instability: A systematic review and meta-analysis

BACKGROUND

The outcomes after mitral valve transcatheter edge-to-edge repair (M-TEER) for the patients with severe mitral regurgitation (MR) in hemodynamically unstable conditions, such as cardiogenic shock, still remain unclear. We aimed to integrate previous publications regarding M-TEER indicated for life-threatening conditions and indirectly particularly compared the short-term outcomes thereof, with that of other treatments.

METHODS

We systematically searched the PubMed, Cochrane, and MEDLINE databases for studies from inception to June 2023, regarding M-TEER in patients with hemodynamic instability and severe MR. The primary outcomes analyzed included the in-hospital and 30-day mortality rates, and peri-procedural complications.

RESULTS

Of the initial 820 publications, we conducted a meta-analysis of a total of 25 studies. The relative risk of moderate-to-severe or severe MR was 0.13 (95 % confidence interval [CI]: 0.10-0.18, I2 = 45.2 %). The pooled in-hospital and 30-day mortality rates were 11.8 % (95 % CI: 8.7-15.9, I2 = 96.4 %) and 14.1 % (95 % CI: 10.9-18.3, I2 = 35.5 %), respectively. The 30-day mortality rate was statistically significantly correlated with the residual moderate-to-severe or severe MR, as per the meta-regression analysis (coefficient β = 3.48 [95 % CI: 0.99-5.97], p = 0.006). Regarding peri-procedural complications, the pooled rates of a stroke or transient ischemic attack, life-threatening or major bleeding, acute kidney injury, and peri-procedural mitral valve surgery were 2.3 % (95 % CI: 1.9-2.6), 7.6 % (95 % CI: 6.8-8.5), 32.9 % (95 % CI: 31.6-34.3), and 1.0 % (95 % CI: 0.8-1.3), respectively.

CONCLUSIONS

This meta-analysis demonstrates that the relatively higher rates of procedural complications were observed, nevertheless, M-TEER can potentially provide favorable short-term outcomes even in hemodynamically unstable patients.

PROSPERO REGISTRATION NUMBER

CRD42023468946.

Left Ventricular Papillary Muscle: Anatomy, Pathophysiology, and Multimodal Evaluation

As an integral part of the mitral valve apparatus, the left ventricle papillary muscle (PM) controls mitral valve closure during systole and participates in the ejection process during left ventricular systole. Mitral regurgitation (MR) is the most immediate and predominant result when the PM is structurally or functionally abnormal. However, dysfunction of the PM is easily underestimated or overlooked in clinical interventions for MR-related diseases. Therefore, adequate recognition of PM dysfunction and PM-derived MR is critical. In this review, we systematically describe the normal anatomical variations in the PM and the pathophysiology of PM dysfunction-related diseases and summarize the commonly used parameters and the advantages and disadvantages of various noninvasive imaging modalities for the structural and functional assessment of the PM.

Management of Severe Mitral Regurgitation in Patients With Acute Myocardial Infarction: JACC Focus Seminar 2/5

Severe acute mitral regurgitation after myocardial infarction includes partial and complete papillary muscle rupture or functional mitral regurgitation. Although its incidence is <1%, mitral regurgitation after acute myocardial infarction frequently causes hemodynamic instability, pulmonary edema, and cardiogenic shock. Medical management has the worst prognosis, and mortality has not changed in decades. Surgery represents the gold standard, but it is associated with high rates of morbidity and mortality. Recently, transcatheter interventions have opened a new door for management that may improve survival. Mechanical circulatory support restores vital organ perfusion and offers the opportunity for a steadier surgical repair. This review focuses on the diagnosis and the interventional management, both surgical and transcatheter, with a glance on future perspectives to enhance patient management and eventually decrease mortality.

Extracorporeal life support in mitral papillary muscle rupture: Outcome of multicenter study

BACKGROUND

Post-acute myocardial infarction papillary muscle rupture (post-AMI PMR) may present variable clinical scenarios and degree of emergency due to result of cardiogenic shock. Veno-arterial extracorporeal life support (V-A ECLS) has been proposed to improve extremely poor pre- or postoperative conditions. Information in this respect is scarce.

METHODS

From the CAUTION (meChanical complicAtion of acUte myocardial infarcTion: an InternatiOnal multiceNter cohort study) database (16 different Centers, data from 2001 to 2018), we extracted adult patients who were surgically treated for post-AMI PMR and underwent pre- or/and postoperative V-A ECLS support. The end-points of this study were in-hospital survival and ECLS complications.

RESULTS

From a total of 214 post-AMI PMR patients submitted to surgery, V-A ECLS was instituted in 23 (11%) patients. The median age was 61.7 years (range 46-81 years). Preoperatively, ECLS was commenced in 10 patients (43.5%), whereas intra/postoperative in the remaining 13. The most common V-A ECLS indication was post-cardiotomy shock, followed by preoperative cardiogenic shock and cardiac arrest. The median duration of V-A ECLS was 4 days. V-A ECLS complications occurred in more than half of the patients. Overall, in-hospital mortality was 39.2% (9/23), compared to 22% (42/219) for the non-ECLS group.

CONCLUSIONS

In post-AMI PMR patients, V-A ECLS was used in almost 10% of the patients either to promote bridge to surgery or as postoperative support. Further investigations are required to better evaluate a potential for increased use and its effects of V-A ECLS in such a context based on the still high perioperative mortality.

MitraClip as bridge to mitral valve replacement in the setting of ischemic cardiogenic shock and papillary muscle rupture

MitraClip implantation has been reported in severe mitral regurgitation following ischemic papillary muscle rupture in surgically high-risk patients with cardiogenic shock. Here we present a case of a 68-year-old female patient who suffered an ischemic papillary muscle rupture resulting in severe mitral prolapse and had a MitraClip implanted. Three months later, due to progressive symptoms, she was taken to surgery and had an elective minimally invasive mitral valve replacement. Informed consent was given and ethics board approval was obtained.

Acute Ischaemic Mitral Valve Regurgitation

Acute ischaemic mitral regurgitation (IMR) is an increasingly rare and challenging complication following acute myocardial infarction. Despite recent technical advances in both surgical and percutaneous interventions, a poor prognosis is often associated with this challenging patient cohort. In this review, we revisit the diagnosis and typical echocardiographic features, and evaluate current surgical and percutaneous treatment options for patients with acute IMR.