Interventional cardiology in cancer patients: A position paper from the Portuguese Cardiovascular Intervention Association and the Portuguese Cardio-Oncology Study Group of the Portuguese Society of Cardiology.

The field of Cardio-Oncology has grown significantly, especially during the last decade. While awareness of cardiotoxicity due to cancer disease and/or therapies has greatly increased, much of the attention has focused on myocardial systolic disfunction and heart failure. However, coronary and structural heart disease are also a common issue in cancer patients and encompass the full spectrum of cardiotoxicity. While invasive percutaneous or surgical intervention, either is often needed or considered in cancer patients, limited evidence or guidelines are available for dealing with coronary or structural heart disease. The Society for Cardiovascular Angiography and Interventions consensus document published in 2016 is the most comprehensive document regarding this particular issue, but relevant evidence has emerged since, which render some of its considerations outdated. In addition to that, the recent 2022 ESC Guidelines on Cardio-Oncology only briefly discuss this topic. As a result, the Portuguese Association of Cardiovascular Intervention and the Cardio-Oncology Study Group of the Portuguese Society of Cardiology have partnered to produce a position paper to address the issue of cardiac intervention in cancer patients, focusing on percutaneous techniques. A brief review of available evidence is provided, followed by practical considerations. These are based both on the literature as well as accumulated experience with these types of patients, as the authors are either interventional cardiologists, cardiologists with experience in the field of Cardio-Oncology, or both.

Acute total occlusion of the unprotected left main coronary artery: Patient characteristics and outcomes.

INTRODUCTION AND OBJECTIVES: Acute total occlusion of the unprotected left main coronary artery (LMCA) is a dramatic event. There are limited data regarding this population. We aimed to describe the clinical presentation and outcomes of patients and to determine predictors of in-hospital mortality. METHODS: This retrospective study included patients presenting with acute (<12 h) myocardial infarction due to total occlusion of the LMCA (TIMI flow 0) between January 2008 and December 2020 in three tertiary hospitals. RESULTS: During this period, 11036 emergent coronary angiographies were performed, 59 (0.5%) of which revealed acute total occlusion of the LMCA. Patients' mean age was 61.2 (SD±12.2) years and 73% were male. No patients had left dominance. At presentation, 73% were in cardiogenic shock, aborted cardiac arrest occurred in 27% and 97% underwent myocardial revascularization. Primary percutaneous coronary intervention was performed in 90% of cases and angiographic success was achieved in 56% of procedures, while 7% of patients underwent surgical revascularization. In-hospital mortality was 58%. Among survivors, 92% and 67% were alive after one and five years, respectively. After multivariate analysis, only cardiogenic shock and angiographic success were independent predictors of in-hospital mortality. Use of mechanical circulatory support and presence of well-developed collateral circulation were not predictive of short-term prognosis. CONCLUSION: Acute total occlusion of the LMCA is associated with a dismal prognosis. Cardiogenic shock and angiographic success play a major role in predicting the prognosis of these patients. The effect of mechanical circulatory support on patient prognosis remains to be determined.

Acute coronary syndrome and stress: Is there a relationship?

INTRODUCTION: Acute coronary syndrome (ACS) is the result of a complex pathophysiological process with various dynamic factors. The 10-item Perceived Stress Scale (PSS-10) is a validated instrument for estimating stress levels in clinical practice and may be useful in the assessment of ACS. METHODS: We carried out a single-center prospective study engaging patients hospitalized with ACS between March 20, 2019 and March 3, 2020. The PSS-10 was completed during the hospitalization period. The ACS group was compared to a control group (the general Portuguese population), and a subanalysis in the stress group were then performed. RESULTS: A total of 171 patients with ACS were included, of whom 36.5% presented ST-elevation myocardial infarction (STEMI), 38.1% were female and the mean PSS score was 19.5±7.1. Females in the control group scored 16.6±6.3 on the PSS-10 and control males scored 13.4±6.5. The female population with ACS scored 22.8±9.8 on the PSS-10 (p<0.001). Similarly, ACS males scored a mean of 17.4±6.4 (p<0.001). Pathological stress levels were not a predictor of major adverse cardiovascular events or severity at admission. CONCLUSIONS: ACS patients had higher perceived stress levels compared to the control group. Perceived stress level was not associated with worse prognosis in ACS patients.

Spontaneous coronary artery dissection: Ten years' experience of a tertiary center.

INTRODUCTION: Spontaneous coronary artery dissection (SCAD) represents 1-4% of all acute coronary syndromes (ACS), and is a particularly important cause among young women and individuals with few cardiovascular risk factors. OBJECTIVES: To characterize clinical background, therapeutic management and clinical outcomes in a SCAD population. METHODS: We retrospectively analyzed all consecutive patients diagnosed with SCAD at a tertiary center between August 2009 and May 2020, with a median follow-up of 40 months (IQR 14-95 months). SCAD was classified according to the Saw angiographic SCAD classification. RESULTS: A total of 36 patients were included, 94% female, mean age 51 years (±11 years). A trigger was only detected in 8% and associated conditions in 31% of patients, mainly inflammatory or autoimmune systemic diseases and migraine. Most patients had non-ST-elevation ACS and 33% presented with ST-elevation ACS. The most frequent culprit lesion was the left anterior descending (LAD) artery (67%); mid to distal segments were the most affected (94%) and type 2 dissection the most prevalent (60%). Almost all patients were successfully medically managed, with only four undergoing percutaneous intervention. During follow-up, ischemic events recurred in 15% of patients and no patient died. Patients with type 2 dissection exhibited lower risk of recurrence compared to type 1 (p=0.049, OR=0.13). CONCLUSION: SCAD patients were mainly young or middle-aged women; the LAD artery was the most affected vessel and type 2 dissection the most prevalent. This report showed for the first time a correlation between type 2 SCAD and lower risk of recurrence.

Percutaneous versus surgical revascularization of unprotected left main coronary artery: Data from the Portuguese Registry of Acute Coronary Syndromes (ProACS).

BACKGROUND: In acute coronary syndromes (ACS), the optimal revascularization strategy for unprotected left main coronary artery (ULMCA) culprit lesion has been under-investigated. Therefore, we compared clinical characteristics and short- and medium-term outcomes of percutaneous and surgical revascularization in ACS. METHODS AND RESULTS: Of 31886 patients enrolled in a multicenter, national, prospective registry study between October 2010 and December 2020, 246 (0.8%) had ULMCA as a culprit lesion and underwent percutaneous coronary intervention (PCI) alone (n=133, 54%) or coronary artery bypass grafting (CABG) alone (n=113, 46%). Patients undergoing PCI presented more frequently ongoing chest pain (68% versus 41%, p<0.001) and cardiogenic shock (25% versus 1%, p<0.001). Time from admission to revascularization was higher in surgical group with a median time to CABG of 4.5 days compared to 0 days to PCI (p<0.001). Angiographic success rate was 93.2% in patients who underwent PCI. Primary endpoint (all-cause death, non-fatal reinfarction and/or non-fatal stroke during hospitalization) occurred in 15.9% of patients and was more frequent in the PCI group (p<0.001). After adjustment, surgical revascularization was associated with better in-hospital prognosis (odds ratio (OR) 0.164; 95% confidence interval (CI), 0.04-0.64; p=0.009). Similar results were achieved after propensity score matching. No difference was found at one-year all-cause death. CONCLUSION: Percutaneous coronary intervention was the most common revascularization strategy in the ACS with ULMCA culprit lesion. PCI was preferred in unstable patients and presented a high angiographic success. CABG was often delayed and preferred in low-risk patients. At one-year follow-up, PCI and CABG conferred a similar prognosis. The two approaches appear complementary in this high risk cohort.

Spontaneous coronary artery dissection: A review for clinical and interventional cardiologists.

Spontaneous coronary artery dissection (SCAD) is an increasingly recognized cause of acute coronary syndrome, especially among young to middle-aged women with few traditional cardiovascular risk factors and low pretest probability for atherosclerotic coronary artery disease. Diagnosis by invasive coronary angiography is the gold standard and conservative therapy is generally recommended, with percutaneous or surgical revascularization being reserved for cases of clinical instability, high-risk anatomy or as bailout. Unlike atherothrombotic coronary artery disease, strong evidence on optimal medical therapy is scarce, posing unique challenges in cases of pregnancy-associated SCAD. The follow-up strategy is also of major importance, as recurrent SCAD is not infrequent, lifestyle changes and pharmacological therapy should be planned for the long term, and SCAD-associated conditions need to be addressed. This review aims to provide a practical management approach to SCAD patients for both clinical and interventional cardiologists.

Cancer patients with acute coronary syndrome have non-superior bleeding risk compared to patients with similar characteristics - a propensity score analysis from the ProACS registry.

INTRODUCTION: The management of acute coronary syndrome (ACS) in malignancy is challenging due to higher bleeding risk. METHODS: We analyzed patients with cancer (active or in the previous five years) prospectively included in the ProACS registry between 2010 and 2019. Our aim was to assess safety (major bleeding, primary endpoint) and secondary efficacy endpoints (in-hospital mortality and combined in-hospital mortality, reinfarction and ischemic stroke) of ACS treatment. Propensity score matching analysis (1:1) was further performed to better understand predictors of outcomes. RESULTS: We found 934 (5%) cancer patients out of a total of 18 845 patients with ACS. Cancer patients had more events: major bleeding (2.9% vs. 1.5%), in-hospital mortality (5.8% vs. 3.4%) and the combined endpoint (7.4% vs. 4.9%). The primary endpoint was related to cancer diagnosis (OR 1.97), previous bleeding (OR 7.09), hemoglobin level (OR 4.94), atrial fibrillation (OR 3.50), oral anticoagulation (OR 3.67) and renal dysfunction. Mortality and the combined secondary endpoint were associated with lower use of invasive coronary angiography and antiplatelet and neurohormonal blocker therapy. After propensity score matching (350 patients), there were no statistically significant differences in endpoints between the populations. CONCLUSION: Bleeding risk was not significant higher in the cancer population compared to patients with similar characteristics, nor were mortality or ischemic risk. The presence of cancer should not preclude simultaneous ACS treatment.

Androgen deprivation therapy mimicking acute coronary syndrome: A case report.

An 80-year-old man diagnosed with prostate cancer and under treatment with androgen deprivation therapy presented at the emergency room with chest pain, repolarization abnormalities and QT interval prolongation on electrocardiogram. An initial diagnosis of acute coronary syndrome was proposed, but biomarkers and coronary angiography were negative. Hydroelectrolyte balance and echocardiogram were also normal. Some weeks after drug withdrawal, repolarization changes reverted. A rare side effect of these drugs mimicking an acute coronary syndrome was the most probable diagnosis.

The impact of the COVID-19 pandemic on acute coronary syndrome admissions to a tertiary care hospital in Portugal.

INTRODUCTION AND OBJECTIVES: The coronavirus SARS-CoV-2 (COVID-19) pandemic has been an unmatched challenge to global healthcare. Although the majority of patients admitted with acute coronary syndrome (ACS) may not be infected with COVID-19, the quarantine and public health emergency measures may have affected this particular high risk group. The objective of this study is to assess the impact of the early period of the COVID-19 pandemic on ACS admissions and clinical course in a tertiary care hospital in Portugal's most affected region. METHODS: This retrospective, case-control study included patients admitted with a diagnosis of ACS during March and April 2020 (pandemic group) and in the same period in 2019 (control group). Clinical course and complications were also assessed. RESULTS: During the pandemic, there were fewer ACS admissions but presentation was more severe, with a larger proportion of acute ST-elevation myocardial infarctions (54.9% vs. 38.8%, p=0.047), higher maximum troponin levels and greater prevalence of left ventricular systolic dysfunction at discharge (58.0% vs. 35.0%, p=0.01). In this population, although not statistically significant, it was observed a delay between the onset of symptoms and percutaneous coronary intervention, which may traduce a deferred search for urgent medical care during the pandemic. CONCLUSION: The lockdown phase of COVID-19 pandemic was associated with fewer and more severe ACS in a Tertiary Care Hospital in Portugal's most affected region by the pandemic.

Acute coronay syndrome in a patient with severe hemophilia A: Dificult decisions.

Hemophilia A is an inherited coagulation disease characterized by factor VIII (FVIII) deficiency and is associated with high hemorrhagic risk, especially in its severe forms. As the average life expectancy of patients with hemophilia has increased, so has the prevalence of acute coronary events. There is however limited experience in dealing with them. The strategy of acting on acute coronary events in patients with hemophilia, as demonstrated in the present case, is a real challenge, not only due to the need for antiplatelet therapy (which is essential in the prevention of stent thrombosis, but increases hemorrhagic risk), but also due to the lack of specific recommendations related to the most adequate and safe replacement therapy in these situations. The authors describe the case of a 48-year-old man with unstable angina and a previous diagnosis of severe hemophilia A who underwent percutaneous coronary intervention under FVIII therapy without hemorrhagic complications.

Eligibility for extended antithrombotic therapy for secondary prevention of acute coronary syndrome.

INTRODUCTION AND OBJECTIVES: Recent randomized controlled trials have evaluated the benefit of extended antithrombotic therapy in secondary prevention of acute coronary syndrome (ACS). However, the numerous and strict enrollment criteria may limit the validity and reproducibility of the published results in clinical practice. Our goal was to estimate the eligibility for participation in two randomized clinical trials in a group of patients followed for ACS. METHODS: We applied the enrollment criteria of two randomized clinical trials (PEGASUS and COMPASS) to consecutive patients who underwent percutaneous coronary intervention in an ACS registry between January 2016 and June 2017. RESULTS: A total of 780 patients were included in the final analysis. The proportion of patients fulfilling the trial enrollment criteria was 35.9% for PEGASUS and 32.1% for COMPASS. The proportion of patients eligible for both trials was 17.7% and 49.7% of patients were eligible for at least one trial. The need for anticoagulant therapy was the most common reason for exclusion on the PEGASUS criteria (46.2%) and the presence of high bleeding risk was the most common reason for exclusion on the COMPASS criteria (61.5%). CONCLUSIONS: Approximately 50% of real-world patients are not eligible for the antithrombotic strategies applied in these trials. Since this non-eligible population is at greater risk of events, further studies are needed to confirm the applicability of these strategies.

Dual antiplatelet therapy in myocardial infarction with non-obstructive coronary artery disease - insights from a nationwide registry.

INTRODUCTION AND OBJECTIVES: Dual antiplatelet therapy (DAPT) is a mainstay for myocardial infarction (MI) therapy. However, in patients with myocardial infarction with non-obstructive coronary artery disease (MINOCA), clear recommendations are lacking in the literature. This study aims to identify the cases in which DAPT is currently prescribed at discharge for MINOCA. METHODS: The authors analyzed a cohort of patients from a multicenter national registry enrolling patients who suffered their first MI between 2010 and 2017, and underwent coronary angiography revealing absence of stenosis ≥50%. Individual antithrombotic therapy was identified. A logistic regression analysis was applied to search for predictors of DAPT. RESULTS: From a total of 16 237 patients analyzed, 709 (4.4%) were categorized as MINOCA. Mean age was 64±13 years, 46.3% (n=409) were females. 390 (55.0%) of MINOCA patients were discharged on DAPT. Males (OR 1.67, CI 95 [1.05-2.38], p=0.027), active smokers (OR=1.82, CI 95 [1.05-3.16], p=0.033), previous percutaneous intervention (OR 3.18, CI 95 [1.48-6.81], p=0.003), ST elevation MI (OR 2.70, CI 95 [1.59-4.76], p<0.001) and sinus rhythm at admission (OR=3.94, CI 95 [2.07-7.48], p<0.001) were independent predictors of DAPT use. CONCLUSION: In this nationwide registry, DAPT was prescribed at discharge in 55% of MINOCA patients. Beyond sinus rhythm, the variables presented as independent predictors for DAPT use identify subgroups of patients who are classified as more prone to thrombotic events. The issue of how to handle antithrombotic agents in MINOCA patients is a topic open for discussion.

Impact of public health initiatives on acute coronary syndrome fatality rates in Portugal.

INTRODUCTION AND OBJECTIVE: Every year cardiovascular disease (CVD) causes 3.9 million deaths in Europe. Portugal has implemented a set of public health policies to tackle CVD mortality: a smoking ban in 2008, a salt reduction regulation in 2010 and the coronary fast-track system (FTS) for acute coronary syndrome (ACS) in 2007. Our goal in this study was to analyze the impact of these three public health policies in reducing case-fatality rates from ACS between 2000 and 2016. METHODS: The impact of these policies on monthly ACS case-fatalities was assessed by creating individual models for each of the initiatives and implementing multiple linear regression analysis, using standard methods for interrupted time series. We also implemented segmented regression analysis to test which year showed a significant difference in the case-fatality slopes. RESULTS: Separate modeling showed that the smoking ban (beta=-0.861, p=0.050) and the FTS (beta=-1.27, p=0.003) had an immediate impact after implementation, but did not have a significant impact on ACS trends. The salt reduction regulation did not have a significant impact. For the segmented model, we found significant differences between case-fatality trends before and after 2009, with rates before 2009 showing a steeper decrease. CONCLUSIONS: The smoking ban and the FTS led to an immediate decrease in case-fatality rates; however, after 2009 no major decrease in case-fatality trends was found. Coronary heart disease constitutes an immense public health problem and it remains essential for decision-makers, public health authorities and the cardiology community to keep working to reduce ACS mortality rates.

Double coronary thrombosis in a patient with Behçet's disease.

Behçet's disease is a chronic relapsing multisystem autoinflammatory condition, in which cardiac involvement is rare, but among the most life-threatening complications. Treatment is largely empirical, and is aimed at suppressing vasculitis. In this role glucocorticoids and colchicine are frequently used. We present the case of a 42-year-old male with previously diagnosed Behçet's disease presenting to our emergency department with an anterior-inferior STEMI. He presented combined thrombosis of the distal anterior descending coronary artery and proximal right coronary artery, and was treated with sequential primary percutaneous coronary interventions and implantation of drug-eluting stents, but required two interventions due to high thrombotic load. His clinical course during hospitalization was good, with no systolic dysfunction at discharge. During follow-up, he has so far had no new cardiovascular events.

Patient and system delays in the treatment of acute coronary syndrome.

INTRODUCTION: Early reperfusion for patients with ST-segment elevation myocardial infarction (STEMI) is indicated by the European Society of Cardiology, while a timely invasive strategy is recommended for patients with high-risk and intermediate-risk non-ST-elevation acute coronary syndromes (NSTE-ACS). This study aims to assess patient and system delays according to diagnosis and risk profile, and to identify predictors of prolonged delay. METHODS: We assembled a cohort of patients (n=939) consecutively admitted to the cardiology department of two hospitals, one in the metropolitan area of Porto and one in the north-east region of Portugal, between August 2013 and December 2014. RESULTS: The proportion of patients with time from symptom onset to first medical contact (FMC) ≥120 min was highest among high-risk NSTE-ACS (57.7%), followed by intermediate-risk NSTE-ACS (52.1%) and STEMI (43.3%). Regardless of diagnosis and risk stratification, use of own transportation and inability to interpret cardiac symptoms correctly were associated with prolonged delays. Regarding system delays, we found that 78.0% of patients with STEMI and 65.8% of patients with high-risk NSTE-ACS were treated in a timeframe exceeding the recommended limits. Admission to a non-percutaneous coronary intervention-capable hospital, admission on weekends and complications at admission were associated with prolonged delays to treatment. CONCLUSIONS: Due to both patient and system delays, a large proportion of STEMI and high-risk NSTE-ACS patients still fail to have access to timely reperfusion.

The prognostic value of elevated matrix metalloproteinase-9 in patients undergoing primary percutaneous coronary intervention for ST-elevation myocardial infarction: A two-year prospective study.

INTRODUCTION: Increased matrix metalloproteinase-9 (MMP-9) levels in ST-elevation myocardial infarction (STEMI) are well established; however, existing data on MMP-9 values as a prognostic marker after STEMI are limited and have been conflicting. OBJECTIVE: This study aimed to assess the clinical significance of MMP-9 in predicting two-year adverse cardiovascular events in patients who underwent primary percutaneous coronary intervention (PCI) after STEMI. METHODS: In this prospective study, 204 patients with STEMI undergoing PCI were included. Participants were classified as high MMP-9 (n=102) or low MMP-9 (n=102) based on a cutoff of 12.92 ng/ml. Both groups were assessed at one and two years after STEMI. RESULTS: Higher cardiovascular mortality at one year was observed in the high MMP-9 group (13.7% vs. 4.9% in the low MMP-9 group, p=0.03). When the follow-up period was extended to two years, the difference in cardiovascular mortality between the groups was more significant (17.6% vs. 4.9%, p=0.004). There was no significant difference at one-year follow-up in rates of advanced heart failure, however at the end of the second year, advanced heart failure was more prevalent in the high MMP-9 group (16.7% vs. 5.9%, p=0.015). After adjustment for potential confounders, a high MMP-9 value had 3.5-fold higher odds for cardiovascular mortality at two-year follow-up than low MMP-9. CONCLUSION: These results suggest that high MMP-9 levels are a strong predictor of cardiovascular mortality and advanced heart failure at two-year follow-up in STEMI patients.

Spontaneous coronary artery dissection: "To stent or not to stent, that is the question". / Disseção coronária espontânea ­ To stent or not to stent that is the question.

Spontaneous coronary artery dissection is a rare cause of acute coronary syndrome that typically occurs in relatively young patients without classical cardiovascular risk factors for coronary artery disease. The etiology appears to be multifactorial and optimal management is not clearly established, so the treatment strategy is often selected based on clinical presentation and coronary anatomy. We present two cases of spontaneous coronary artery dissection with different initial approaches, highlighting the importance of a case-by-case assessment.

A rare cause of acute coronary syndromes in young adults - myeloproliferative neoplasms: A case series.

INTRODUCTION: Acute coronary syndromes (ACS) mostly occur in patients with traditional risk factors. Especially in young adults without major cardiovascular (CV) risk factors, one of the less common causes of ACS is myeloproliferative neoplasms (MPNs). METHODS: We retrospectively collected data on 11 consecutive patients (nine men, two women, mean age 40.18±8.4 years) with a diagnosis of MPN who presented with ACS. The demographic characteristics of the study population, type of MPN, clinical manifestations, location of myocardial infarction (MI), coronary angiography findings, complete blood count and other related findings, and treatment strategy before and after diagnosis were analyzed. RESULTS: Six patients were diagnosed with polycythemia vera, four with essential thrombocytosis and one with primary myelofibrosis. A JAK2 mutation was found in nine patients. Mean time to diagnosis of MPN was 2.81 years after presenting ACS and mean age at first MI was 32.9±6 years. Six patients had no major CV risk factors. Ten patients had anterior MI and one had inferior MI. After initiation of specific treatment for MPN, no recurrent thrombotic events were observed in a mean follow-up of 4±2.44 years. CONCLUSIONS: In young adults presenting with ACS, MPNs should be considered, especially in the absence of atherosclerotic coronary artery lesions. It is also important to pay attention to blood cell count abnormalities seen in intracoronary thrombotic events. Early diagnosis and treatment of MPNs is essential to prevent recurrence of thrombotic events and may reduce mortality and morbidity related to thrombotic complications.

Fenómeno de Milking secundario a puente intramiocárdico en paciente con bloqueo trifascicular

Introducción: los puentes intramiocárdicos son una modificación anatómica de la circulación coronaria que consisten en secciones anormales en el espesor del miocardio que al formar segmentos tunelizados e incorporarse al epicardio, provocan un ordeñamiento vascular llamado fenómeno de Milking durante la compresión sistólica extrínseca, el cual es responsable de las manifestaciones clínicas y las alteraciones electrocardiográficas. Se describe un caso clínico con el objetivo de comunicar a la comunidad científica las características clínicas, eléctricas y coronariográficas de una paciente con síndrome coronario agudo con bloqueo trifascicular y fenómeno de Milking por puente intramiocárdico. Caso clínico: mujer de56 años, con antecedentes de hipertensión arterial, obesidad e historia de ingresos frecuentes por episodios de angina inestables; fue admitida por angina inestable aguda más bloqueo trifascicular y se confirmó puente intramiocárdico en el segmento medio distal de la arteria descendente anterior izquierda. La optimización de la terapia antiisquémica se basó en Carvedilol, previa implantación de marcapaso permanente. Discusión: los puentes intramiocárdicos causan reducción dinámica de la luz del vaso epicárdico coronario y cuando resulta mayor del 50% condiciona el fenómeno de Milking, el cual es más frecuente en los segmentos medio y distal de la arteria descendente anterior izquierda, su evolución es favorable y responden a la terapéutica con ß bloqueadores de forma adecuada. Conclusiones: la correlación diagnóstica facilitó la aplicación de una conducta invasiva con estimulación transvenosa permanente que permitió iniciar tratamiento betabloqueante lo cual no hubiera sido posible por el trastorno de la conducción intraventricular.

Introduction: Intramyocardial bridges are an anatomical modification of the coronary circulation consisting of abnormal sections in the thickness of the myocardium that, when forming tunnel segments and incorporating into the epicardium, cause vascular milking, the so-called milking phenomenon, during extrinsic systolic compression, which is responsible for the clinical manifestations and electrocardiographic alterations. A clinical case is described with the aim of providing the scientific community with the clinical, electrical and coronary angiographic characteristics of a patient with acute coronary syndrome with trifascicular block and milking phenomenon due to intramyocardial bridging. Case Report: A 56-year-old woman with a history of hypertension, obesity, and frequent admissions for episodes of unstable angina was admitted for acute unstable angina plus trifascicular block and intramyocardial bridging was confirmed in the distal middle segment of the left anterior descending artery. Optimization of anti-ischemic therapy was based on carvedilol after implantation of a permanent pacemaker. Discussion: Intramyocardial bridges cause a dynamic reduction of the coronary epicardial vessel lumen and when it is greater than 50% it causes a milking phenomenon, which is more frequent in the middle and distal segments of the left anterior descending artery, its evolution is favorable and responds adequately to ß-blocker therapy. Conclusions: The diagnostic correlation facilitated the application of an invasive approach with permanent transvenous stimulation, allowing the initiation of beta-blocker treatment, which would not have been possible due to the intraventricular conduction disorder.

Introdução: As pontes intramiocárdicas são uma modificação anatómica da circulação coronária constituída por secções anómalas na espessura do miocárdio que, ao formarem segmentos em túnel e ao incorporarem-se no epicárdio, provocam a ordenha vascular, o chamado fenómeno de ordenha, durante a compressão sistólica extrínseca, responsável pelas manifestações clínicas e alterações electrocardiográficas. Descreve-se um caso clínico como objetivo de dar a conhecer à comunidade científica as características clínicas, eléctricas e coronariográficas de um doente com síndrome coronário agudo com bloqueio trifascicular e fenómeno de milking por bridging intramiocárdico. Relato de Caso: Mulher de 56 anos, com antecedentes de hipertensão arterial, obesidade e internamentos frequentes por episódios de angina instável, foi internada por angina aguda instável com bloqueio trifascicular e confirmação de ponte intramiocárdica no segmento médio distal da artéria descendente anterior. A otimização da terapêutica anti-isquémica foi baseada no carvedilol após implantação de pacemaker definitivo. Discussão: As pontes intramiocárdicas provocam uma redução dinâmica do lúmen do vaso epicárdico coronário e quando esta é superior a 50% provoca um fenómeno de ordenha, mais frequente nos segmentos médio e distal da artéria descendente anterior, a sua evolução é favorável e responde adequadamente à terapêutica com ß-bloqueantes. Conclusões: A correlação diagnóstica facilitou a aplicação de uma abordagem invasiva com estimulação transvenosa permanente, permitindo o início do tratamento com beta-bloqueadores, o que não teria sido possível devido ao distúrbio de condução intraventricular.

Effect of beta-blocker dose on mortality after acute coronary syndrome.

INTRODUCTION: Beta-blocker doses that have been shown to be effective in randomized clinical trials are not commonly used in daily clinical practice. The aim of this study was to analyze whether there is a prognostic benefit of high rather than low doses of beta-blockers after an acute coronary syndrome (ACS). METHODS: In this retrospective cohort study, 2092 ACS patients discharged from hospital between June 2013 and January 2016 were classified according to the beta-blocker dose prescribed: high dose (≥50% of the target dose tested in clinical trials) and low dose (<50%). Two groups of 501 matched patients were obtained through propensity score matching according to treatment with high or low doses of beta-blockers. The prognostic impact (mortality) during follow-up of high vs. low dose was analyzed by Cox regression and represented by Kaplan-Meier curves. RESULTS: Of the 2092 patients, 80.5% were discharged under beta-blockers, with lower mortality during follow-up (18.6±9.7 months). Of the 1685 patients discharged under beta-blockers, only 31.4% received high doses. There were no differences in mortality during follow-up between patients under high-dose vs. low-dose beta-blockers (HR 0.935, 95% CI 0.628-1.392, p=0.740), and the equivalence between the two doses remained after propensity score matching (HR 1.183, 95% CI 0.715-1.958, p=0.513). CONCLUSION: No prognostic benefit was found in terms of mortality for high-dose vs. low-dose beta-blockers after an ACS.