In the past year, significant progress has been achieved in percutaneous coronary interventions (PCI), in interventions for structural heart diseases, and in supportive pharmacotherapy. These advancements have taken place despite the continuous burden on healthcare workers and systems caused by the COVID-19 pandemic.
There are still a number of controversial and unresolved issues in some fields of interventional cardiology, which have been discussed by Escaned et al. in a review article (1) in this issue of Cardiologia Croatica, who provide an overview of recent studies and beneficial changes in clinical practice, with the goal of optimizing the outcomes of percutaneous interventions.
One of the open and unsolved questions is application of complete myocardial revascularization in patients with acute coronary syndrome (ACS) and multivessel coronary heart disease. Current clinical practice and guidelines indicated only revascularization of “culprit” lesions was necessary in ST-segment elevation myocardial infarction (STEMI), excepting patients in cardiogenic shock. Based on recent research, the revascularization of “non-culprit” lesions has become a realistic option. It is important to note that there is no evidence on the benefits of assessing the functional significance of lesions. Angiographically guided PCI of tight “non-culprit” lesions (>70%) in blood vessels with a >2 mm diameter is thus indicated in all patients with STEMI, regardless of fractional flow reserve (FFR) values.
Revascularization remains an important and controversial topic in multivessel coronary heart disease. On the one hand, the results of the SYNTAX II study (2) have shown the non-inferiority of the “SYNTAX II strategy” during 5-year follow-up of surgical myocardial revascularization. On the other hand, the results of the FAME III study (3) did not demonstrate non-inferiority of FFR-guided PCI in comparison with cardiosurgical treatment. There is thus no doubt that further research is required to provide answers to these still-unresolved questions.
Technological progress in the field of drug-eluting stents has enabled us to use stents with ultra-thin struts to further reduce post-interventional risk of unwanted cardiovascular events.
Treatment of small diameter coronary arteries remains a significant challenge, and avoiding stents in such situations has become increasingly common. This treatment preference has been supported by recent studies, since the continuous effectiveness and safety of drug-coated balloons has been demonstrated in comparison with drug-eluting stents for newly-formed lesions in small diameter coronary arteries.
As for complex coronary lesions, most studies still support the strategy of placing 1 stent whenever possible in interventions on the left main coronary artery involving its bifurcations.
For chronic total occlusions (CTO), every patient requires a selective approach, with additional clarification on who, when, and why as well as standardization of procedures and performance techniques.
A trend towards the reintroduction of atherectomy has been observed (especially in the USA), as well as intravascular lithotripsy in patients with severe calcified newly-formed lesions as part of PCI treatment.
With regard to intravascular imaging, recent studies have shown consistently reduced rates of unwanted cardiovascular events if PCI is guided by intravascular ultrasound in comparison with interventions guided solely by angiography.
The first clinical study on the benefits of applying functional coronary angiography (noninvasive fractional flow reserve derived from coronary CT angiography) for guided PCI drew special attention, as it demonstrated reduced frequency of severe unwanted cardiovascular events when PCI was performed using this technology.
Increasing attention is being directed at atherosclerotic plaque, especially the presence of thin-cap fibroatheroma (TCFA) <65 µm in relationship to the functional assessment of stenosis significance. The COMBINE OCT-FFR study (4) demonstrated that the combination of negative FFR and presence of TCFA plaque had significantly higher incidence of unwanted cardiovascular events in comparison with negative FFR and TCFA plaque.
In the field of transcatheter therapy for aortic valve stenosis, a comparison was performed between the newest generations of different types of transcatheter biological valves (self-expandable vs. balloon-expandable), and no difference was found in the frequency of total unwanted cardiovascular events.
In contrast, “silent” ischemic brain damage was detected using magnetic resonance imaging in >80% of patients treated with transcatheter aortic valve implantation (TAVI). In order to prevent clinically significant and “silent” brain lesions, cerebral protection devices during TAVI were examined, but no clear benefit was found in their routine application, so they should be applied selectively at best.
Studies on the long-term comparative characteristics of TAVI and surgical aortic valve replacement (SAVR) in the population of low-risk patients with aortic valve stenosis showed that TAVI is now also a treatment option for patients with low risk with longer life expectancy.
Recent ESC/EACTS guidlelines (5) emphasize the importance of patient age when deciding between TAVI and SAVR, with TAVI being recommended for patients aged ≥75 regardless of surgical risk as well as for asymptomatic patients with severe aortic valve stenosis and left ventricular dysfunction (EF <50%).
Regarding adjuvant pharmacotherapy in interventional cardiology, studies have demonstrated the benefit of reduced duration dual antiplatelet therapy in patients with high risk of bleeding undergoing PCI, but with additional caution being necessary in ACS patients.
As for antiplatelet therapy in patients undergoing TAVI, studies have indicated that antiplatelet monotherapy should remain the standard treatment regimen when there is no indication for DAPT or systemic antiplatelet therapy.
In conclusion, I would like to emphasize that the review presented in this issue (1) is a valuable source of information that integrates a wealth of clinical studies from almost all fields in interventional cardiology. I hope you will find it useful in your everyday practice and that it will enable you to achieve the best treatment results with the lowest rate of complications, all with the goal of providing the best and most modern medical care for our patients.