European Registry On Plaque ModifiCAtion in the STEMI Population (ROCA-STEMI)

The ROCA-STEMI study is an European prospective cohort study from February 2023 until February 2024. The investigators want to analyze the clinical success, efficacy and safety of consecutive patients who presented with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) for de novo heavily calcified culprit lesion using plaque modification devices before stent implantation.

Clinical and angiographic endpoints will be defined according to the recommendations of the Academic Research Consortium. Academic Research Consortium represents a step toward standardization, facilitating the evaluation of the safety and effectiveness of devices.

Bleeding as a safety endpoint will be defined according to the Bleeding Academic Research Consortium. Major bleeding will be defined as Bleeding Academic Research Consortium types 3 and 5.

Severe coronary calcified lesion: Imaging evidence of severe calcium at the culprit lesion site was based on the angiographic presence of radio-opacities noted without cardiac motion before contrast injection involving both sides of the arterial wall in at least 1 location, or presence of ≥270° of calcium at 1 cross-section through IVUS.

Major adverse cardiovascular events (MACE): will be defined as the composite of cardiac death; MI; stroke, and revascularization, including percutaneous coronary intervention, and coronary artery bypass graft. Deaths will be regarded to be attributable to a cardiac cause unless a non-cardiac death could be confirmed.

Target lesion revascularization (TLR): will be defined as repeat PCI to treat the same lesion treated during the index procedure.

Target vessel revascularization (TVR): will be defined as PCI of a new severe lesion at another location other than the segment vessel treated at the index PCI.

Non-TVR: will be defined as PCI of a different vessel treated at the index procedure.

Target-lesion failure (TLF): will be defined as the composite of clinically-driven TLR, myocardial infarction, or cardiac death related to the target vessel.

Segment treated thrombosis (STT): is defined according to the Academic Research Consortium (ARC) definition as definite, probable, or possible and as early (0 to 30 days), late (31 to 360 days), or very late (>360 days).

Acute closure: is defined as the occurrence of new, severely reduced flow (grade 0 or 1, according to the Thrombolysis in Myocardial Infarction (TIMI) within the target vessel during the intervention that persists and requires another kind of treatment or results in MI or death.

Study device and procedures

Interventional procedure All coronary calcified lesions will be treated using at least one plaque-modification device. The concomitant use of other plaque-modification devices will be allowed in the presence of heavy calcium and at the operator's discretion.

Based on technology without balloon: rotational atherectomy (RA), orbital atherectomy (OA) and excimer laser coronary atherectomy (ELCA). Among devices based on technologies with balloon there are the cutting balloon, the scoring balloon, the coronary lithoplasty balloon (CL) and the super-high-pressure twin layer non-compliant (NC) balloon, OPN.

Cutting balloon and scoring balloon. The WOLVERINE cutting balloon (Boston Scientific, Marlborough, MA, United States) consists of a NC balloon with 3 micro-blades longitudinally arranged on its surface. Sequential inflation up to 6 atm is advisable. Other available devices are the AngioSculpt, Scoreflex, and NSE Alpha scoring balloons.

Shockwave Coronary IVL System. The lithoplasty balloon (LB) is a rapid-exchange balloon catheter with emitters that generate sonic waves to crack the calcium and to improve vessel compliance. The LB is inflated at calcified lesion level at a pressure of 4 atm and 1 Hz shockwaves are administered. Once the LB is on the lesion, it is connected to an external unit that generates pulsatile mechanical waves. The LB is initially inflated at a pressure of 4 atm and 10 pulses are administered (around 10 seconds are required). Then, the LB is inflated at a 6 atm pressure and then it is deflated to restore the flow. New cycles are then applied; a total of 8 therapies (80 pulses) per balloon and lesion can be administered. Due to its size, if the length of the lesion is > 12 mm, the LB can be repositioned to treat the lesion entirely.

Rotational atherectomy (RA): is an endovascular procedure to modify atherosclerotic plaque by advancing a diamond-coated rotating metal olive-shaped burr. The rotational speed recommended is between 135.000 rpm and 180.000 rpm. Decelerations > 5000 rpm should be avoided. The burr should be advanced gradually with easy back-and-forth moves and rotablation time should be < 20 seconds with pauses in between each cycle. Once rotablation has been performed, the olive-shaped burr is removed and the Dynaglide mode is activated.

Orbital atherectomy (OA): is an endovascular procedure to modify atherosclerotic plaque by using a diamond-coated crown whose mechanism of action consists of the antegrade and retrograde modification of the plaque.14-16 The OA mechanism of action is the elliptical rotation of the crown that gradually increases orbital diameter as rotation speed increases from 80.000 rpm to 120.000 rpm. The OA effect is time-dependent; 30 second-cycles are advisable with 30 second-pauses in between them. The continuous infusion of a lubricant solution (ViperSlide) is required to minimize thermal lesions during OA; also, 18 mL/min of fluid are administered to cool the device down and eliminate residue, thus reducing ischemia and distal embolization.

Excimer laser coronary atherectomy (ELCA): The Philips CVX-300 ELCA system uses xenon chloride and emits pulses of ultraviolet (UV) light at a 308-nm wavelength. The UV pulses generated only penetrate 50 μm deep, which disintegrates the calcified plaque through a mechanism of ablation without damage to the middle or adventitia layers.29,30 There are 4 different sizes of ELCA monorail catheter available (0.9, 0.14, 1.7 and 2.0 mm) that can be advanced on a 0.014 in guidewire. The right size is selected on a 0.5:0.6 ratio between catheter and vessel. Slowly moving the device forward promotes an increased luminal gain at lesion level. The number of pulses, length and total time of ELCA treatment should be individualized depending on the characteristics of the lesion. The particles generated have a diameter < 10 μm so they are reabsorbed by the reticuloendothelial system, thus avoiding microvascular obstruction.

The implantation of a drug-eluting stent (DES) is then performed at the discretion of the operator along with high-pressure (>16 atm) postdilation. Dual-antiplatelet therapy will be administered following the established clinical practice guidelines.

Clinical and angiographic data Clinical data and clinical events will be investigator-reported through an electronic case report form (eCRF). Detailed outcome definitions have been described previously.

Angiographic analysis the presence of severe coronary calcification was evaluated, based on coronary angiography, during the index procedure by each investigator at the participating centers.

Ethics Aspects The study will be conducted according to the ethical principles derived from the Declaration of Helsinki (Fortaleza, Brazil, October 2013), ISO 14155, and clinical practice guidelines. In addition, the study will be conducted according to the protocol of Good Clinical Practice (GCP) following the International Conference on Harmonization (ICH) guidelines and regulatory requirements for participating institutions. The study protocol was approved by the Institutional Ethics Committee and the hospital's research commission. Once a patient has been identified as a candidate for participation in the study (meeting all inclusion criteria and none exclusion criteria), and after duly informing the patient about the characteristics of the study, an informed consent will be signed and recorded in the corresponding file of the center's investigator. Baseline demographics, procedural features, clinical outcomes and follow-up data will be collected by the coinvestigators at each institution through dedicated electronic case report form (e-CRF).