In-hospital Outcomes of Rotational Atherectomy in ST-Elevation Myocardial Infarction: Results From the Multicentre ROTA-STEMI Network.

BACKGROUND: Although the use of rotational atherectomy (RA) is off-label in the setting of ST-elevation myocardial infarction (STEMI), it can be the only option in severely calcified culprit lesions to achieve procedural success. We sought to investigate the safety and feasibility of RA during primary percutaneous coronary intervention (PPCI). METHODS: This was a retrospective observational study of patients who underwent RA during PPCI from 12 European centres. The main outcomes were procedural success (defined as successful stent implantation with final thrombolysis in myocardial infarction [TIMI] flow 3 and residual stenosis < 30%) and in-hospital mortality. A comparison of patients presenting with and without shock was performed. RESULTS: In 104 patients with RA during STEMI, the mean age was 72.8 ± 9.1 years, and 35% presented with cardiogenic shock. Bailout RA was performed in 76.9% of cases. Mean burr size was 1.42 ± 0.21 mm. Procedural success was achieved in 86.5% of cases, with no difference between shocked and nonshocked patients (94.4% vs 82.4%; P = 0.13). In-hospital stent thrombosis occurred in 0.96%, perforation in 1.9% and burr entrapment in 2.9% of cases. In spite of equally high procedural success, in-hospital mortality was higher in shocked (50%) compared with nonshocked patients (1.5%; P < 0.0001). CONCLUSIONS: Patients presenting with STEMI requiring RA, represent a high-risk population, frequently presenting with cardiogenic shock. In this analysis of selected patients, RA was performed as a bailout strategy in the majority, and, as such, RA seems to be feasible with a high procedural success rate. In the absence of cardiogenic shock, RA-facilitated PCI seems to be associated with low in-hospital mortality.

Diseases of the Coronary Microcirculation: Diagnosis and Treatment.

BACKGROUND: Coronary microvascular dysfunction (CMD) comprises a variety of pathogenic mechanisms that impair the microcirculation of the heart. Clinical studies have shown that 30-50% of patients suffering from myocardial ischemia without significant coronary artery stenosis have CMD. The disease is associated with ele - vated mortality and poor quality of life. Whenever a patient presents with symptoms of angina pectoris and no underlying disease is detected by the usual methods, CMD should be considered a possible cause. METHODS: This review is based on publications retrieved by a selective search in PubMed and on current international guidelines and recommendations of specialty societies. RESULTS: The diagnosis of CMD is based on objective evidence of a microvascular origin of symptoms. The guidelines contain a class IIa recommendation for invasive coronary flow reserve and microvascular resistance measurements. Noninvasive tests such as positron emission tomography and cardiac magnetic resonance imaging are less accurate and are given a class IIb recommendation. No highquality therapeutic trials are available to date, and the treatment of CMD is thus based on that of chronic coronary syndrome. Lifestyle modification is performed to reduce risk factors. Patients with an abnormal coronary flow reserve or elevated microvascular resistance can be treated with an ACE inhibitor or angiotensin receptor blocker. Beta-blockers and calcium channel antagonists can relieve angina pectoris. Statins lower the LDL level and have positive pleiotropic effects. First-line treatment can be supplemented with further medications. CONCLUSION: Approximately 25% of patients with CMD have symptoms that do not respond to intensive treatment with the currently available modalities. New treatments, including interventional therapies, are being studied. Their long-term benefit remains to be assessed and compared to that of the existing methods.

Coronary Venous Pressure and Microvascular Hemodynamics in Patients With Microvascular Angina: A Randomized Clinical Trial.

Importance: The role of the coronary venous circulation in regulating myocardial perfusion and its potential in treating microvascular angina is unexplored. Objective: To evaluate whether an increase in coronary venous pressure modifies microvascular resistance in patients with microvascular angina. Design, Setting, and Participants: This was a blinded, sham-controlled, crossover, randomized clinical trial that enrolled participants between November 2021 and January 2023. Participants for this physiology end point study were recruited from the Cardiology Center of the University of Medicine in Mainz, Germany. Patients with moderate/severe angina pectoris (Canadian Cardiovascular Society class 2-4) due to microvascular dysfunction (as defined by the thermodilution-based index of microvascular resistance >25 mm Hg × s). Exclusion criteria were epicardial coronary disease, second- and third-degree atrioventricular block, severe valvular heart disease, cardiomyopathy, and pulmonary or kidney disease. Intervention: Inflation of an undersized balloon placed in the cardiac coronary sinus (CS), hereafter referred to as balloon and the deflated balloon in the right atrium, referred to as sham. Measurements were performed at rest and during maximal coronary hyperemia. Both patients and final assessors were blinded to the randomization sequence. Main Outcomes and Measures: Hemodynamic parameters, including aortic (Pa) and distal (Pd) coronary pressure, coronary sinus pressure (Pcs), right atrial pressure (Pra), and the mean transit time (inverse of blood flow [Tmn]), were measured. Results: A total of 20 patients (median [IQR] age, 69 [64-75] years; 11 female [55.0%]) were included in the study. Two patients (10%) had diabetes, 6 (30%) had hypercholesterolemia, 15 (75%) had hypertension, and 3 (15%) were active smokers. The inflation of the CS balloon caused a significant increase in CS pressure at rest and during hyperemia (300% and 317% increase, respectively, compared with sham, both P < .001), a decrease in hyperemic distal coronary pressure (median [IQR], sham: 92 [80-100] mm Hg; balloon: 79 [75-93] mm Hg; P = .01) and mean transit time (sham: 0.39 [0.23-0.62] s; balloon: 0.26 [0.17-0.46] s; P = .008). As a result, CS occlusion led to a decrease in both resting coronary resistance (median [IQR], sham: 59 [37-87] mm Hg × s; balloon: 42 [31-67] mm Hg × s; P = .005) and the primary end point hyperemic coronary resistance (mean [IQR], sham: 31 [23-53] mm Hg × s; balloon: 14 [8-26] mm Hg × s; P < .001). Conclusion and Relevance: Increased coronary venous pressure led to a reduction of microvascular resistances in patients with microvascular angina, a mechanism with potential implications for the therapy of this complex disease. Trial Registration: ClinicalTrials.gov Identifier: NCT05034224.

Six-months clinical and intracoronary imaging follow-up after reverse T and protrusion or double-kissing and crush stenting for the treatment of complex left main bifurcation lesions.

Background: There is a debate regarding the best stent strategy for unprotected distal left main (LM) bifurcation disease. Among two-stent techniques, double-kissing and crush (DKC) is favored in current guidelines but is complex and requires expertise. Reverse T and Protrusion (rTAP) was shown to be a comparable strategy regarding short-term efficacy and safety, but with reduced procedural complexity. Aim: To compare rTAP vs. DKC by optical coherence tomography (OCT) on the intermediate term. Methods: 52 consecutive patients with complex unprotected LM stenoses (Medina 0,1,1 or 1,1,1) were randomized to either DKC or rTAP and followed-up for a median of 189[180-263] days for clinical and OCT outcomes. Results: At follow-up OCT showed similar change in the side branch (SB) ostial area (primary endpoint). The confluence polygon showed a higher percentage of malapposed stent struts in the rTAP group that did not reach statistical significance (rTAP: 9.7[4.4-18.3] % vs. DKC: 3[0.07-10.9] %; p = 0.064). It also showed a trend towards larger neointimal area relative to the stent area (DKC: 8.8 [6.9 to 13.4] % vs. rTAP: 6.5 [3.9 to 8.9] %; p = 0.07), and smaller luminal area (DKC: 9.54[8.09-11.07] mm2 vs. rTAP: 11.21[9.53-12.42] mm²; p = 0.09) in the DKC group. The minimum luminal area in the parent vessel distal to the bifurcation was significantly smaller in the DKC group (DKC: 4.64 [3.64 to 5.34] mm² vs. rTAP: 6.76 [5.20 to 7.29] mm²; p = 0.03). This segment also showed a trend for smaller stent areas (p = 0.05 to 0.09), and a bigger neointimal area relative to the stent area (DKC: 8.94 [5.43 to 10.5]% vs. rTAP: 4.75 [0.08 to 8.5]%; p = 0.06) in the DKC patients. The incidence of clinical events was comparably low in both groups. Conclusion: At 6-months, OCT showed a similar change in the SB ostial area (primary endpoint) in rTAP compared to DKC. There was also a trend for smaller luminal areas in the confluence polygon and the distal parent vessel, and a larger neointimal area relative to the stent area, in DKC, along with a tendency for more malapposed stent struts in rTAP. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT03714750, identifier: NCT03714750.

Randomized, crossover, controlled trial on the modulation of cardiac coronary sinus hemodynamics to develop a new treatment for microvascular disease: Protocol of the MACCUS trial.

Background: Microvascular angina (MVA) is a frequent condition for which our understanding of the disease pathophysiology and therapeutic perspectives remain unsatisfactory. The current study is designed to test whether an improvement in microvascular resistances could be achieved by elevating backward pressure in the coronary venous system, based on the hypothesis that an increase in hydrostatic pressure could cause a dilatation of the myocardial arterioles, resulting in a reduction of vascular resistances. This approach might have potential clinical implications, as it might suggest that interventions aimed at increasing coronary sinus (CS) pressure might result in a decrease in angina in this subset of patients. The aim of our single-center, sham-controlled, crossover randomized trial is to investigate the effect of an acute increase in CS pressure on a number of parameters of coronary physiology, including parameters of coronary microvascular resistance and conductance. Methods and analysis: A total of 20 consecutive patients with angina pectoris and coronary microvascular dysfunction (CMD) will be enrolled in the study. Hemodynamic parameters including aortic and distal coronary pressure, CS and right atrial pressure, and the coronary microvascular resistance index will be measured at rest and during hyperemia in a randomized crossover design during incomplete balloon occlusion ("balloon") and with the deflated balloon in the right atrium ("sham"). The primary end point of the study is the change in index of microvascular resistances (IMR) after acute modulation of CS pressure, while key secondary end points include changes in the other parameters. Discussion: The aim of the study is to investigate whether occlusion of the CS is associated with a decrease in IMR. The results will provide mechanistic evidence for the development of a treatment for patients with MVA. Clinical trial registration: https://clinicaltrials.gov/, identifier NCT05034224.

Quantitative Flow Ratio or Angiography for the Assessment of Non-culprit Lesions in Acute Coronary Syndromes: Protocol of the Randomized Trial QUOMODO.

Background: Approximately 50% of the patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndromes (ACS) have additional stenotic lesions in non-infarct-related coronary arteries. The decision whether these stenoses require further treatment is routinely based on angiography alone. The quantitative flow ratio (QFR) is a simple non-invasive method that may help quantify the functional significance of these intermediate coronary artery lesions. The aim of our single-center, randomized superiority trial is to test the impact and efficacy of QFR, as compared to angiography, in the treatment of patients with ACS with multivessel coronary artery disease. Primary goal of the study is to investigate 1. The impact of QFR on the proportion of patients receiving PCI vs. conservative therapy and 2. whether QFR improves angina pectoris and overall cardiovascular outcomes. Methods and Analysis: After treatment of the culprit lesion(s), a total of 200 consecutive ACS patients will be randomized 1:1 to angiography- vs. QFR-guided revascularization of non-culprit stenoses. Patients and clinicians responsible are blinded to the randomization group. The primary functional endpoint is defined as the proportion of patients assigned to medical treatment in the two groups. The primary clinical endpoint is a composite of death, non-fatal myocardial infarction, revascularization and significant angina at 12 months. Secondary endpoints include changes in the SAQ subgroups, and clinical events at 3- and 12-month follow-up. Discussion: This study is designed to investigate whether QFR-based decision-making is associated with a decrease in angina and an improved prognosis in patients with multivessel disease. Trial Registration Number: ClinicalTrials.gov Registry (NCT04808310).

Randomized non-inferiority TrIal comParing reverse T And Protrusion versus double-kissing and crush Stenting for the treatment of complex left main bifurcation lesions.

BACKGROUND: The treatment of left main bifurcation stenoses remains challenging. AIMS: We compare the "Reverse T and Protrusion" (reverse-TAP) technique to Double-Kissing and crush (DK-crush). METHODS: The study was designed as non-inferiority trial, the primary endpoint was percentage stent expansion in the ostial side branch at optical coherence tomography. RESULTS: 52 consecutive patients (13 females, 17 diabetics, Syntax score 25 [22-29]) with complex coronary bifurcation lesions of the left main were randomized in a 1:1 ratio to Reverse-TAP or DK-crush stenting. The intervention was performed according to protocol in all patients in both randomization groups. Side branch stent expansion was 75 [67-90]% in the DK-crush group and 86 [75-95]% in the reverse-TAP group (one-sided 97.5% lower parametric confidence interval: - 0.28%; P < 0.01 for non-inferiority; P = 0.037 for superiority). Side branch balloon pressure during final kissing was higher in the DK-crush group (14 [12-16] vs. reverse-TAP: 13 [12-14]; P = 0.043). Procedural time was shorter with reverse-TAP (DK-crush: 32 [24-44] min vs reverse-TAP: 25 [22-33] min; P = 0.044). Other procedural parameters were not different between groups. There was no difference in any of the safety endpoints up to 1 month. CONCLUSIONS: A reverse-TAP strategy for the interventional treatment of complex coronary lesions was non-inferior and superior to DK-crush for the primary endpoint side branch expansion while requiring less time. A larger study testing long-term clinical outcomes is warranted. TRAIL REGISTRATION: NCT: NCT03714750.

Effectiveness of a Real-Time X-ray Dosimetry Monitor in Reducing Radiation Exposure in Coronary Procedures: The ESPRESSO-Raysafe Randomized Trial.

Background-Several methods to reduce radiation exposure in the setting of coronary procedures are available on the market, and we previously showed that additional radiation shields reduce operator exposure during radial interventions. We set out to examine the efficacy of real-time personal dosimetry monitoring in a real-world setting of radial artery catheterization. Methods and Results-In an all-comer prospective, parallel study, consecutive coronary diagnostic and intervention procedures were performed with the use of standard radiation shield alone (control group) or with the addition of a real-time dosimetry monitoring system (Raysafe, Billdal, Sweden, monitoring group). The primary outcome was the difference in exposure of the primary operator among groups. Additional endpoints included patient, nurse, second operator exposure and fluoroscopy time. A total of 700 procedures were included in the analysis (n = 369 in the monitoring group). There were no differences among groups in patients' body mass index (p = 0.232), type of procedure (intervention vs. diagnostic, p = 0.172), and patient sex (p = 0.784). Fluoroscopy time was shorter in the monitoring group (5.6 (5.1-6.2) min vs. 7.0 (6.1-7.7) min, p = 0.023). Radiation exposure was significantly lower in the monitoring group for the patient (135 (115-151) µSv vs. 208 (176-245) µSv, p < 0.0001) but not for the first operator (9 (7-11) µSv vs. 10 (8-11), p = 0.70) and the assistant (2 (1-2) µSv vs. 2 (1-2) µSv, p = 0.121). Conclusions-In clinical daily practice, the use of a real-time dosimetry monitoring device reduces patient radiation exposure and fluoroscopy time without an effect on operator radiation exposure.

Coronary In-Stent Restenosis: Predictors and Treatment.

BACKGROUND: Despite the use of modern drug-eluting stents (DES), in-stent restenosis (ISR) may still occur in as many as 2-10% of percutaneous coronary interventions (PCI) in certain lesion/patient subsets. ISR causes increased morbidity after stent implantation; acute myocardial infarction is a frequent correlate to a clinical ISR, arising in 5-10% of cases. Compared to de novo stenosis, patients with ISR also present more frequently with symptoms of unstable angina pectoris (45% versus 61%). In this article, we discuss the risk factors for ISR and the corresponding diagnostic measures and effective treatment strategies. METHODS: This review is based on pertinent publications retrieved by a selective search in PubMed, with special attention to current international guidelines and specialist society recommendations. RESULTS: The type of implanted stent, the presence of diabetes mellitus, previous bypass surgery, and small vessel caliber are predictors for ISR. In their guidelines, the European specialist societies (ESC/EACTS) recommend repeated PCI with DES implantation or drug-coated balloon (DCB) angioplasty as the methods of choice for the treatment of ISR. This approach is supported by evidence from meta-analyses. The RIBS-IV trial showed that revascularization treatment of the target lesion is needed less often after everolimus-eluting stent (EES) implantation than after DCB dilatation (11 [7.1%] versus 24 [15.6%]; p = 0.015; hazard ratio: 0.43; 95% confidence interval: [0.21; 0.87]). CONCLUSION: Because the pathogenesis of ISR is multifactorial, differentiated risk stratification is necessary. The identification of patient-, stent-, and lesion-related predictors is particularly important, as the most effective way to combat ISR is to prevent it.