Nenad Bozinovic

Background: Advancing the retrograde microcatheter (MC) into the antegrade guide catheter during retrograde chronic total occlusion (CTO) percutaneous coronary intervention (PCI) can be challenging or impossible, preventing guidewire externalization. Objectives: To detail and evaluate all the techniques focused on wiring to achieve intubation of the distal tip of a microcatheter, balloon, or stent with an antegrade or retrograde guidewire, aiming to reduce complications by minimizing tension on fragile collaterals during externalization and enabling rapid antegrade conversion in various clinical scenarios. Methods: We describe the two main techniques, tip‐in and rendezvous, and their derivatives such a facilitated tip‐in, manual MC‐tip modification, tip‐in the balloon, tip‐in the stent, deep dive rendezvous, catch‐it and antegrade microcatheter probing. We provide case studies that demonstrate the effectiveness of these techniques in complex scenarios involving extreme vessel angulation, severe calcification, fragile collaterals, and challenging retrograde MC crossing without externalization. Conclusion: The development of advanced variants along with traditional techniques to establish retrograde guidewire connection and antegrade conversion has led to the establishment of a cohesive group of methods known as portal techniques. These approaches serve as strategic advantages in retrograde CTO‐PCI, providing a valuable and feasible alternative to conventional retrograde connection techniques, particularly when those techniques fail. Their ability to avoid the externalization process reduces potential damage to collateral channels and the ostium of the donor artery, potentially leading to a reduction in complication rates.

Background: The recent development and widespread adoption of antegrade dissection re‐entry (ADR) techniques have been underlined as one of the antegrade strategies in all worldwide CTO consensus documents. However, historical wire‐based ADR experience has suffered from disappointing long‐term outcomes.Aims: Compare technical success, procedural success, and long‐term outcome of patients who underwent wire‐based ADR technique versus antegrade wiring (AW).Methods: One thousand seven hundred and ten patients, from the prospective European Registry of Chronic Total Occlusions (ERCTO), underwent 1806 CTO procedures between January 2018 and December 2021, at 13 high‐volume ADR centers. Among all 1806 lesions attempted by the antegrade approach, 72% were approached with AW techniques and 28% with wire‐based ADR techniques.Results: Technical and procedural success rates were lower in wire‐based ADR than in AW (90.3% vs. 96.4%, p < 0.001; 87.7% vs. 95.4%, p < 0.001, respectively); however, wire‐based ADR was used successfully more often in complex lesions as compared to AW (p = 0.017). Wire‐based ADR was used in most cases (85%) after failure of AW or retrograde procedures. At a mean clinical follow‐up of 21 ± 15 months, major adverse cardiac and cerebrovascular events (MACCEs) did not differ between AW and wire‐based ADR (12% vs. 15.1%, p = 0.106); both AW and wire‐based ADR procedures were associated with significant symptom improvements.Conclusions: As compared to AW, wire‐based ADR is a reliable and effective strategy successfully used in more complex lesions and often after the failure of other techniques. At long‐term follow‐up, patient's MACCEs and symptoms improvement were similar in both antegrade techniques.

Introduction. Kounis syndrome is a simultaneous manifestation of acute coronary syndrome with conditions associated with mast cell activation, such as allergies or anaphylactic reactions. We present early stent thrombosis in female with atopic constitution without previous aterosclerosis of coronary arteries. Case report. A 50-year-old female with typical anginal pain was addmited to Clinic for Cardiology, UCC Niš. She had passed by a linden tree in bloom, few hrs before, and immediately after felt chest pain, paresthesia and numbnes in her left hand, throat tightness, heaviness of the tongue, and swelling of the lips. Symptoms stopped for 60 min after taking 10 mg of loratadine. 30 min after addmision ECG showed ST elevation in D2, D3, aVF, V6. She underwent an emergency percutaneous coronary intervention (PCI) procedure. Occlusive thrombosis was seen in the ostium of the left anterior descending (LAD) coronary artery. Sirolimus-coated stent was placed with Thrombolysis in Myocardial Infarction (TIMI) 3 flow obtained. A few hrs later, patient reported a new onset of chest pain followed by ventrucular fibrilation (VF), DC shock and occurence of new ST segment elevation in aVR, V1-V3. Repeated angiography showed acute in-stent trombotic occlusion. Baloon angioplasty was performed which restored TIMI 3 flow in LAD. Anticoagulant and corticosteroid therapy was administered. Three days following an intervention, optical coherence tomography (OCT) imiging showed no signs of aterosclerosis and restenosis, adequate stent expansion and apposition. Conclusion. Coronary agiography proved type I Kounis syndrome after the exposure to an allergen, and type III Kounis syndrome developed shortly after stent placement. Newly described causes of acute and subacute stent thrombosis in type III Kounis syndrome are stent-associated hypersensitivity reactions.

Introduction. Myocarditis is a common diagnosis, but its etiology often remains unknown as it requires extensive diagnostic work. Eosinophilic granulomatosis with polyangiitis (EGPA) or Churg-Strauss syndrome is a very rare systemic disease, which is not easy to diagnose. Myocarditis in EGPA is not common and it usually occurs in the late stages of the disease. Case report. A 22-year-old man was admitted as acute coronary syndrome (ACS). Coronary angiography was performed and excluded stenosis of epicardial coronary arteries. The working diagnosis of myocardial infarction with non-obstructive coronary arteries (MINOCA) was established. Then we found inflammatory syndrome, eosinophilia and a lot of systemic symptoms and signs. We managed to establish the diagnosis of myopericarditis by cardiac magnetic resonance imaging (MRI). The diagnostic workout included extensive laboratory tests, which ruled out infectious agents. Then, immunological tests, a computed tomography (CT) scan of the chest, and a biopsy of the bone marrow, nasal mucosa, and skin were performed. The cause of myocarditis - EGPA, was found only after the histopathological finding of the skin biopsy, which enabled adequate immunosuppressive therapy. Conclusion. The accurate diagnosis was crucial for the correct-causal treatment of the patient, especially since he needs life-long immunosuppressive therapy. For such complex patients, a multidisciplinary approach and perseverance in the diagnostic evaluation of the etiology of myocarditis are necessary for adequate treatment.

Cardiac disease and cancer are two of the leading causes of morbidity and mortality worldwide. The development of screening, diagnosis and treatment of both diseases and also primary and secondary prevention has resulted in an increase of cancer survivors with concomitant cardiovascular diseases. Cancer patients are on increased risk of CAD and ACS. Chemo and radiation therapy induced coronary artery injury and the increased risk of thrombosis result in higher risk of cardiovascular morbidity and mortality rate. Conservative approach in treatment of patients with ACS and any type of malignancies do not improve survival rates. In the majority of cancer patients with acceptable prognosis or cancer survivors, well planned and performed PCI is probably the best option. Physicians and medical stuff must be aware of the potential complications of cancer therapies. The management of cancer patients with acute and chronic coronary artery diseases should be individualized and discussed within the acute cardiooncology team. In terms of limited evidences, future studies are needed for investigation of well-balanced treatment strategies and improvement in survival outcome.

Objective. A case report of a patient with acute coronary syndrome with occlusion of the left main coronary artery with a typical clinical picture and a negative exercise stres test result.Case report. A 44-year-old patient is presented to our service as STEMI with elevation in the inferior leads and ST depression in the precordial leads. After intrahospital cardiac arrest and resuscitation, primary PCI of left main coronary artery is performed, after which hemodynamic stabilization occurs. Retrospective review of medical history reveals that he was evaluated three years before the acute event due to occasional chest pain. The pretest probability for coronary heart disease was 38%, so in accordance with the then valid ESC guidelines for stable coronary heart disease, a stress ECG test was performed, which was assessed as negative for significant coronary heart disease. All analyzed test parameters indicated a low risk of adverse cardiovascular events: functional capacity, ST segment denivelation, chronotropic competence, blood pressure variations, Duke treadmill score. With a postest probability of 9%, the patient was not further evaluated for coronary heart disease and was asymptomatic for the next three years and did not respond to follow-up examinations. If he presented himself after 2019 according to the newer ESC guidelines for chronic coronary syndromes, the patient would be indicated to perform a functional imaging test or CT coronary angiography at the time of the initial clinical evaluation.Conclusion. The diagnostic algorithm for patients with chest pain is based on a pretest probability that determines further diagnostic workup. Patients with a negative exercise test and a typical clinical presentation should be referred for further diagnostic imaging test because of the risk that a small number of them may have significant and even critical coronary stenosis.