Fractional flow reserve to guide surgical coronary revascularization

A case report of myocardial ischemia improvement despite early bypass graft occlusion: Efficiency of physiological reassessment

Patients with functional ischemia often do not complain of chest symptoms even in early occlusion after coronary artery bypass grafting (CABG). The clinical evidence indicating the necessity of revascularization for these patients is unclear. A 70-year-old man who underwent 3 stent implant procedures to treat repeated in-stent restenosis to the left anterior descending artery (LAD) felt effort-related chest pain. Coronary angiography revealed that the patient's jailed diagonal had severe stenosis with delay and the LAD had intermediate stenosis. The instantaneous wave-free ratio (iFR) value of the LAD equalled 0.75. The patient underwent sequential CABG, where the left internal mammary artery (LIMA) to the LAD and diagonal artery grafts were performed. Although his effort-related chest pain disappeared, coronary and bypass angiography did not show flow competition in the diagonal branch and early occlusion in the LIMA to LAD graft was confirmed. The physiological assessment of the LAD did not reveal myocardial ischemia (iFR = 0.89 and fractional flow reserve = 0.87). This case highlights the importance of physiological assessment to detect cases of early graft occlusion. Although the LAD was not perfused from the CABG, the iFR value improved dramatically and pharmacological therapy without revascularization was successful for this patient. .

The role of Cardiac Magnetic Resonance (CMR) in the diagnosis of cardiomyopathy: A systematic review

Background

Myocardial pathologies are significant causes of morbidity and mortality in patients worldwide. Ischemic and non-ischemic cardiomyopathies have become a worldwide epidemic of the 21st century with an increasing impact on health care systems. The 2012 European Society of Cardiology and 2013 American College of Cardiology Foundation/American Heart Association guidelines provide current therapy guidance to reduce mortality and morbidity.

Methods

This was a systematic review involving cardiac magnetic resonance (CMR) studies for the diagnosis of cardiomyopathy from January 2013 to April 2017. Out of 62 reviewed studies, only 12 were included in our study.

Results

The average sensitivity and specificity of CMR in the diagnosis of cardiomyopathy was 86.75% (95% confidence interval [CI], 70.30% to 92.58%) and 81.75% (95% CI, 73.0% to 87.6%), respectively, and the positive predictive and negative predictive values were 80.17% and 86.75%, respectively.

Conclusion

Despite some limitations, our study shows that CMR has high sensitivity, specificity, and positive predictive value in diagnosing different types of cardiomyopathy. CMR may be used to differentiate types of cardiomyopathy, accurately quantify the chamber dimensions, volumes, and cardiac function, which make it useful for prognosis as well.

The role of cardiac magnetic resonance (CMR) in the diagnosis of cardiomyopathy: A systematic review

Background

Myocardial pathologies are significant causes of morbidity and mortality in patients worldwide. Ischemic and non-ischemic cardiomyopathies have become a worldwide epidemic of the 21st century with an increasing impact on health care systems. The 2012 European Society of Cardiology and 2013 American College of Cardiology Foundation/American Heart Association guidelines provide current therapy guidance to reduce mortality and morbidity.

Methods

This was a systematic review involving cardiac magnetic resonance (CMR) studies for the diagnosis of cardiomyopathy from January 2013 to April 2017. Out of 62 reviewed studies, only 12 were included in our study.

Results

The average sensitivity and specificity of CMR in the diagnosis of cardiomyopathy was 86.75% (95% confidence interval [CI], 70.30% to 92.58%) and 81.75% (95% CI, 73.0% to 87.6%), respectively, and the positive predictive and negative predictive values were 80.17% and 86.75%, respectively.

Conclusion

Despite some limitations, our study shows that CMR has high sensitivity, specificity, and positive predictive value in diagnosing different types of cardiomyopathy. CMR may be used to differentiate types of cardiomyopathy, accurately quantify the chamber dimensions, volumes, and cardiac function, which make it useful for prognosis as well.

One-Year Follow-Up Results From the Observational, Multicenter, Prospective, and Controlled Registry: The WALTZ All-Comers Study

The aim of this study was to evaluate 1-year follow-up results in an all “comers” population treated with a new cobalt chromium bare-metal stent (BMS) design. Since August 2016 to March 2017, 201 (9.7% of screening population) consecutive patients undergoing coronary stent implantation in 11 centers in Argentina were prospectively included in our registry. The inclusion criteria were multiple-vessel disease and/or unprotected left main disease, acute coronary syndromes (ACS) with at least one severe (⩾70%) stenosis in any of major epicardial vessel. In-stent restenosis, protected left main stenosis, or impossibility to receive dual-antiplatelet therapy was an exclusion criterion. Major adverse cardiac events (MACE) were the primary endpoint and included cardiac death, myocardial infarction (MI), and target lesion revascularization (TLR); also, all components of the primary endpoint were separately analyzed. Completeness of revascularization was analyzed as post hoc data using residual SYNTAX or ERACI risk scores. Demographic characteristics showed that 6.5% of patients were very elderly, 22.5% have diabetes, 47% have multiple-vessel disease, 67% have ACS, and 32% have ST elevation MI. At a mean of 376 ± 18.1 days of follow-up, MACE was observed in 10.4% of patients: death + MI + cardiovascular accident (CVA) in 3% (6 of 201) and cardiac death + MI + CVA in 1.5% (3 of 201). Residual ERACI score ⩽5 was associated with 98% of event-free survival (P < .04). In conclusion, this prospective, multicenter, and observational all-comers registry with this novel BMS design showed a low incidence of adverse events at 1 year mainly due to coronary restenosis.

Physiologic assessment of moderate coronary lesions: a step towards complete revascularization in coronary artery bypass grafting

Background

An accurate diagnostic assessment of coronary artery disease is crucial for patients undergoing coronary artery bypass grafting (CABG). Fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) to guide complete revascularization have not been adequately studied in patients prior to CABG. We compared an anatomic to a physiologic assessment of moderate coronary lesions (40-70% stenosis) in patients referred for CABG.

Methods

We retrospectively reviewed 109 medical records of patients who underwent CABG at Tulane Medical Center from 2014 to 2016. Patients were divided into an FFR/iFR-guided and an angiography-guided group. Clinical characteristics, procedural outcomes, and clinical outcomes for the two groups were compared over an 18-month follow-up period.

Results

There were significantly higher rates of three-vessel anastomoses (85.7% vs. 74.7%, P<0.05) and venous grafting (85.7% vs. 76.8%, P<0.05) in the FFR/iFR group. The FFR/iFR group had a lower rate of grafts placed to the left anterior descending artery (LAD) distribution than the angiography group (7.1% vs. 29.5%, P<0.05). The FFR/iFR group had a higher rate of grafts placed to the left circumflex (LCx) artery distribution than the angiography group (28.6% vs. 9.5%, P<0.05). We observed a trend toward reduction in major adverse cardiac events (MACEs) (7.1% vs. 11.6%, P=0.369) and angina (0.0% vs. 6.3%, P=0.429) in the FFR/iFR group compared to the angiography group over 18 months.

Conclusions

Physiologic assessment of coronary lesions can effectively guide complete revascularization in patients undergoing CABG. Moreover, FFR/iFR-guided CABG was associated with significantly higher rates of three-vessel anastomoses, venous grafting, and graft distribution to the circumflex system.

Should functional assessment of lesion severity be used to guide coronary bypass?

PURPOSE OF REVIEW

The purpose of this article is to investigate the potential role of fractional flow reserve (FFR) to guide surgical revascularization.

RECENT FINDINGS

Coronary artery bypass is planned and executed primarily based on angiographic coronary anatomy. FFR is the most well-established tool for functional assessment of coronary lesions. Randomized trials have demonstrated the benefit of FFR-guided percutaneous coronary intervention (PCI) to determine the ischemic burden of intermediate lesions. Surgically, FFR is predominantly used to determine the functional severity of intermediate lesions of the left anterior descending (LAD) coronary artery to establish candidacy for multivessel coronary bypass. The broader use of FFR will likely downgrade a proportion of coronary lesions, which may alter the overall management plan. Whether this will improve clinical outcomes remains to be seen. Importantly, bypass of functionally nonsignificant lesions predicts graft failure. However, graft failure in the context of sufficient native coronary flow may not impact negatively on clinical outcome. Thus, at this time, there are insufficient data to support the wider use of FFR to guide surgical grafting of non-LAD targets. It remains to be seen whether FFR can be used to optimize the use of arterial grafts or to guide complex revascularization strategies such as hybrid coronary revascularization.

SUMMARY

FFR has become an invaluable tool for decision making for PCI in patients with stable ischemic heart disease. Beyond its use to assess an intermediate LAD lesion to establish candidacy for coronary bypass, at present there are insufficient data to support its wider use to guide surgical revascularization.

Coronary Surgery in Women and the Challenges We Face

This review was undertaken to understand the dynamics that have shaped our current treatment of women who undergo coronary artery bypass grafting (CABG) and summarize the current literature on surgical revascularization in women. There has been improved access to CABG over the past several decades. Despite this, compared with men, CABG in women involves fewer grafts and less frequent use of arterial grafts, the latter having improved long-term patency compared with saphenous vein grafts. We attempt to determine whether the adverse clinical profile of women, when referred for CABG is responsible for this finding. Female coronary anatomy and pathophysiology are reviewed and an attempt is made to understand how this might affect decisions of selection and outcome measures post CABG. We review the short-term, long-term, and quality of life outcomes in women. These data are taken from large databases, as well as from more recent publications. Randomized controlled trial data and meta-analytic data are used when available. Differential use of and outcomes of surgical strategies, including off-pump CABG and total arterial revascularization, are contrasted with those in men. This review shows that there continues to be widespread differences in surgical approach to coronary artery disease in female vs male patients. We provide evidence suggestive of the existence of issues specific to women that affect selection for surgical procedures and outcomes in women. More work is required to understand the reason for these differences and how to optimize sex-specific outcomes.