Percutaneous Coronary Intervention with Procedural Unfractionated Heparin without Activated Clotting Time Guidance: A Unique Opportunity to Assess Thrombotic and Bleeding Events.

Background: Rates of major bleeding and intraprocedural thrombotic events (IPTE) in the setting of percutaneous coronary intervention (PCI) using weight-adjusted unfractionated heparin (UFH) without activated clotting time (ACT) monitoring are not known. Methods: We reviewed 2,748 consecutive patients who underwent coronary angiography at our tertiary care university hospital between January 2017 and December 2020. All patients who underwent PCI with weight-adjusted UFH without ACT guidance were considered for further analysis. Major bleeding complications occurring within 48 hours of PCI were collected from patients' medical records. IPTE were collected independently by two interventional cardiologists after review of coronary angiograms. Results: There were 718 patients included in the analysis (65.4 ± 12.2 years old; 81.3% male). In total, 45 patients (7.8%) experienced a major bleed or IPTE. The most common IPTE were slow/no reflow (1.5%) and coronary artery dissection with decreased flow (1.1%). Other IPTE occurred in <1% of cases. Major bleeding occurred in 11 patients (1.5%), of whom 8 required blood transfusion and 3 required vascular intervention. Bleeding complications were more common with femoral compared with radial access (6.6% vs. 0.2%, P < 0.001). Conclusion: Weight-adjusted UFH use during PCI without ACT monitoring was related to low rates of major bleeding or IPTE.

Emergency Medical Services Utilization and Outcomes of Patients with ST-Elevation Myocardial Infarction in Lebanon.

BACKGROUND: Arrival of patients with ST-elevation myocardial infarction (STEMI) by Emergency Medical Services (EMS) results in shorter reperfusion times and lower mortality in developed countries. OBJECTIVES: This study examines EMS use by STEMI patients in Lebanon and associated clinical outcomes. METHODS: A retrospective observational study with chart review was carried out for STEMI patients arriving to the Emergency Department of a tertiary care center in Lebanon between January 1, 2013 and August 31, 2016. A descriptive analysis was done and followed by a bivariate analysis comparing two groups of patients (EMS vs. Non-EMS). RESULTS: A total of 280 patients were included in the study. They were mostly male (71.8%). Mean age was 65.1 years (95% confidence interval [CI] 63.4-66.9). Only 12.5% (95% CI 8.6-16.4) presented by EMS. Chest pain (81.1%) was the most common presenting symptom. Anterior myocardial infarction was the most common electrocardiogram (ECG) diagnosis (51.4%). Most patients were admitted (98.2%), and 72.0% of these patients were treated with primary percutaneous coronary intervention. Cardiogenic shock was the most frequent in-hospital complication (6.2%). The mortality rate was 7.1%. Mean door-to-ECG and door-to-balloon times were 10.8 (95% CI 7.1-14.4) min and 106.2 (95% CI 95.9-116.6) min, respectively. Patients' characteristics, presenting symptoms, outcomes, and performance metrics were similar between the two groups. CONCLUSION: EMS is underutilized by STEMI patients in Lebanon and is not associated with improvement in clinical outcomes. Medical oversight and quality initiatives focusing on outcomes of patients with timely sensitive emergencies are needed to advance the prehospital care system in Lebanon.

The Mutation P.T613a in the Pore Helix of the Kv 11.1 Potassium Channel is Associated with Long QT Syndrome.

BACKGROUND: Loss-of-function mutations in the voltage gated potassium channel Kv 11.1 have been associated with the Long QT Syndrome (LQTS) type 2. We identified the p.T613A mutation in Kv 11.1 in a family with LQTS. T613A is located in the outer part of the pore helix, a structure that is involved in C-type inactivation. Here we characterize the effect of p.T613A on the functional properties of KV 11.1. METHODS: The p.T613A mutation was introduced into KV 11.1 (T613A). Wild-type KV 11.1 (WT) and T613A were expressed in Xenopus laevis oocytes and characterized by two-electrode-voltage-clamp. RESULTS: T613A currents were reduced to <20% of WT currents and T613A induced a minor negative shift in half maximal rectification, indicating that the voltage-dependent onset on inactivation occurred at more negative voltages compared to WT. Co-expression of T613A with WT revealed intermediate phenotype and there was no dominant negative effect of T613A. CONCLUSION: These findings suggest that p.T613A causes a loss-of-function of Kv 11.1. This results in a reduced repolarizing reserve which may result in LQTS2 and sudden cardiac death.

Short-Term Clinical Outcomes of Transcatheter Aortic Valve Replacement in a Developing Country.

INTRODUCTION: Transcatheter aortic valve replacement (TAVR) is an effective alternative to surgical aortic valve replacement (SAVR) in patients with severe aortic stenosis in all surgical risk groups. Reports of clinical outcomes post-TAVR in developing countries are scarce. We aimed to address the clinical outcomes and safety profile of TAVR in a developing country. METHODS: We conducted a single-center, retrospective study on patients undergoing TAVR at the American University of Beirut Medical Center (AUBMC) from January 2016 to April 2023. We included a total of 399 patients. Our primary endpoint was to assess the rate of TAVR in-hospital and 30-day mortality, neurologic events, and new permanent pacemaker implantation (PPI) in patients, stratified by the Society of Thoracic Surgeons (STS) risk of mortality score. RESULTS: Survival rates were 98.7% (394) at discharge vs. 97.5% (389) at 30 days post-procedure. The technical success rate was 95% (379) at the end of the procedure. Device success and early safety rates were 93.5% (373) and 83% (331), respectively at 30 days post-procedure. The all-cause mortality rate increased from 1.3% (5) at discharge to 2.5% (10) at 30-day intervals. The rate of ischemic stroke was 1.3% (five) at discharge and increased to 2% (eight) at 30 days post-procedure. PPI was needed in 5.8% (23) of patients at discharge with an increase to 7% (28) at one-month interval. Overall, the rates of TAVR outcomes among the three risk groups were comparable including neurologic events, valve-related complications, bleeding problems, vascular and access-related complications, and myocardial infarction. CONCLUSION: This study at AUBMC highlights the successful implementation of the TAVR program in a developing country, showcasing its efficacy and safety within 30 days post-operation, despite challenges such as financial constraints and limited access to specialized training. Larger cohorts and longer follow-up periods are needed to accurately represent clinical outcomes in developing countries.

Structural valve deterioration of the Labcor Dokimos aortic prosthesis: a single-centre experience.

OBJECTIVES: The goal of this study was to assess the performance and incidence of the deterioration of the Labcor Dokimos bioprosthetic aortic valve. METHODS: We performed a retrospective medical chart review of 116 patients who underwent surgical aortic valve replacement with the Labcor Dokimos aortic valve between 2010 and 2018. Abstracted data included patient demographic and echocardiographic data. Patients were divided into 2 groups: patients with structural valve deterioration (SVD) and patients without SVD. RESULTS: Among the patients with complete follow-up (n = 95), 10 patients were excluded because they died within a year; 85 patients were included in the final analysis. Of the 85 patients, 32 (38%) developed SVD; 22 (26%) had severe SVD, 15 (18%) of whom underwent reintervention. The most common aetiology of SVD was severe central aortic regurgitation, which was detected in 91% of the patients who had severe SVD. The average time from operation to severe SVD was 4.7 years with a minimum of 1.5 years and a maximum of 7.9 years. CONCLUSIONS: Bioprosthetic aortic valve deterioration due to severe aortic regurgitation is common and occurs early with the Labcor Dokimos valve. This occurrence needs to be furthered investigated in larger registries.

Epidemiology, etiology, and outcomes of in-hospital cardiac arrest in Lebanon.

BACKGROUND: In-hospital cardiac arrest (IHCA) constitutes a significant cause of morbidity and mortality. As data is scarce in the Middle East and Lebanon, we devised this study to shed some light on it to better inform both hospitals and policymakers about the magnitude and quality of IHCA care in Lebanon. METHODS: We analyzed retrospective data from 680 IHCA events at the American University of Beirut Medical Center between July 1, 2016 and May 2, 2019. Sociodemographic variables included age and sex, in addition to the comorbidities listed in the Charlson comorbidity index. IHCA event variables were day, event location, time from activation to arrival, initial cardiac rhythm, and the total number of IHCA events. We also looked at the months and years. We considered the return of spontaneous circulation (ROSC) and survival to discharge (StD) to be our outcomes of interest. RESULTS: The incidence of IHCA was 6.58 per 1,000 hospital admissions (95% CI: 6.09-7.08). Non-shockable rhythms were 90.7% of IHCAs. Most IHCA cases occurred in the closed units (87.9%) (intensive care unit, respiratory care unit, neurology care unit, and cardiology care unit) and on weekdays (76.5%). ROSC followed more than half the IHCA events (56%). However, only 5.4% of IHCA events achieved StD. Both ROSC and StD were higher in cases with a shockable rhythm. Survival outcomes were not significantly different between day, evening, and nightshifts. ROSC was not significantly different between weekdays and weekends; however, StD was higher in events that happened during weekdays than weekends (6.7%vs. 1.9%, P = 0.002). CONCLUSIONS: The incidence of IHCA was high, and its outcomes were lower compared to other developed countries. Survival outcomes were better for patients who had a shockable rhythm and were similar between the time of day and days of the week. These findings may help inform hospitals and policymakers about the magnitude and quality of IHCA care in Lebanon.

Change in cardiac troponin T level after intravitreal anti-vascular endothelial growth factor treatment: Prospective pilot study.

BACKGROUND: Evaluate subclinical myocardial injury associated with intravitreal anti-vascular endothelial growth factor therapy by measuring serum high-sensitivity cardiac troponin T. METHODS: This is a prospective pilot comparative study conducted at American University of Beirut Medical Center, Beirut, Lebanon. In total, 40 consecutive patients were randomized to receive either intravitreal bevacizumab or ranibizumab. Patients received three consecutive monthly injections of the assigned drug, then continued treatment as needed. Systemic concentrations of high-sensitivity cardiac troponin T and vascular endothelial growth factor were obtained at baseline, week 9, and week 24. Primary endpoint measure was change in high-sensitivity cardiac troponin T levels compared to baseline. Secondary endpoint measure was change in systemic vascular endothelial growth factor levels. RESULTS: There was no significant difference in high-sensitivity cardiac troponin T levels over time (p = 0.227) within each treatment group and no significant difference between treatments at any time point (p = 0.276). There was a significant decrease in plasma vascular endothelial growth factor levels at week 9 (p = 0.001) and week 24 (p < 0.001) compared to baseline. In the ranibizumab group, vascular endothelial growth factor levels were not significantly different at weeks 9 and 24 compared to baseline (p = 0.708 and p = 0.117, respectively). There was a significant association between the number of bevacizumab injections from weeks 8 to 24 and the decrease in vascular endothelial growth factor levels at week 24 (R = -0.67, p = 0.032). This correlation was not observed in the ranibizumab group (R = -0.341, p = 0.141). CONCLUSION: Repeated intravitreal bevacizumab or ranibizumab did not influence serum high-sensitivity cardiac troponin levels. Intravitreal bevacizumab but not ranibizumab lowered free-systemic vascular endothelial growth factor levels, which was observed in this study to be inversely related to the number of bevacizumab injections.

Comparison of the systemic levels of inflammatory markers after percutaneous coronary intervention with bare metal versus sirolimus-eluting stents.

BACKGROUND: Percutaneous coronary intervention (PCI) with bare metal stent (BMS) deployment causes plaque disruption and a rise in systemic levels of C-reactive protein (CRP), interleukin (IL)-6, and monocyte chemoattractant protein (MCP)-1. Our aim is to study whether PCI with sirolimus-eluting stent (SES) use attenuates this response. METHODS: Patients with stable angina undergoing single-vessel PCI were enrolled in a randomized, open-label fashion into a BMS group or an SES group. Blood samples were drawn pre-PCI, 24 hours post-PCI, and 30 days post-PCI. Systemic concentrations of CRP, IL-6, and MCP-1 were measured at all time points. RESULTS: In total, 41 patients were enrolled (21 in the BMS group and 20 in the SES group). The baseline plasma concentrations of all markers were comparable between groups. At 24 hours, the mean plasma CRP concentration in the SES group was 20.21 mg/dL versus 8.95 mg/dL in the BMS group (P = 0.15). The mean plasma IL-6 concentration at 24 hours was 25.41 pg/mL in the SES group versus 17.44 pg/mL in the BMS group (P = 0.17). The mean plasma MCP-1 concentration at 24 hours was 382.38 pg/mL in the SES group versus 329.04 pg/mL in the BMS group (P = 0.2). At 30 days, plasma concentrations of all three markers decreased to similar values between groups. CONCLUSIONS: The use of SES did not inhibit the rise in systemic concentrations of CRP, IL-6, and MCP-1 at 24 hours or 30 days post-PCI, compared with BMS. Moreover, at 24 hours, there was a trend for higher systemic levels of all proinflammatory markers in the SES group compared with the BMS cohort.

Mutations in the ABCG8 gene are associated with sitosterolaemia in the homozygous form and xanthelasmas in the heterozygous form.

Sitosterol is the most abundant plant sterol found in our diet. Sitosterolemia (OMIM 210250), also known as phytosterolaemia, is a rare autosomal recessive disease caused by the inability to efficiently excrete plant sterol, and is characterized by cutaneous xanthomas and accelerated atherosclerosis. Sitosterolaemia is caused by homozygous or compound heterozygous mutations in either ABCG5 or ABCG8 (both on chromosome 2p21), which encode the sterol efflux transporter ABCG5 (sterolin-1) and ABCG8 (sterolin-2), respectively. To investigate a Tunisian family with several members who manifested with generalized cutaneous xanthomas, whereas others had only isolated xanthelasmas. Genetic analysis was performed based on exome sequencing of DNA obtained from five affected individuals and one unaffected individual from a Tunisian family. RESULTS: A novel mutation in the ABCG8 gene, designated c.965-1G>C, was identified by exome sequencing in the members of this family. The homozygous form was associated with generalized cutaneous xanthomatosis while the heterozygous form was linked to isolated xanthelasmas. Our results indicate a gene dosage effect of ABCG8 and suggest that individuals at risk should be followed closely.

Comparison of ST-segment resolution with combined fibrinolytic and glycoprotein IIb/IIIa inhibitor therapy versus fibrinolytic alone (data from four clinical trials).

We compared combination fibrinolytic plus glycoprotein IIb/IIIa inhibitor therapy with stand-alone fibrinolysis with respect to speed and stability of reperfusion in patients who had acute ST-segment elevation myocardial infarction; data were obtained from 654 patients in 4 trials (Integrilin to Manage Platelet Aggregation to Combat Thrombosis in Acute Myocardial Infarction, Platelet Aggregation Receptor Antagonist Dose Investigation and Reperfusion Gain in Myocardial Infarction, Integrilin and Tenecteplase in Acute Myocardial Infarction, and the Fifth Global Use of Strategies to Open Occluded Coronary Arteries) that compared thrombolytics plus lamifiban, eptifibatide, or abciximab with standard thrombolysis. We found significantly faster and more stable ST-segment recovery with combination therapy starting at 60 minutes (56.7% vs 48.0% with >/=50% ST-segment resolution, p = 0.03) and sustained over 180 minutes after drug administration; this transient benefit may suggest a time frame when more optimal percutaneous coronary intervention can be performed.

Interventional cardiovascular pharmacotherapy: current issues.

In the last decade, a variety of novel anticoagulant and antiplatelet agents that improve outcomes in patients undergoing percutaneous coronary revascularization have emerged. During the next decade, continued refinements in catheter-based device technology should lead to further increases in the number of interventional procedures. The use of optimal antithrombotic strategies is pivotal in reducing adverse events among patients undergoing percutaneous coronary intervention (PCI). Our purpose is to review the current evidence regarding the efficacy of available adjunctive anticoagulant and antiplatelet agents in treating patients undergoing percutaneous coronary revascularization. It should be borne in mind that patients undergoing PCI in the midst of an acute coronary event require a different level of coagulation and platelet aggregation inhibition than low-risk patients undergoing elective PCI for stable angina pectoris. Similarly, generalizing antithrombotic regimen safety data to a wide spectrum of catheter-based therapeutic devices should be avoided. A level of anticoagulation that is safe and effective for angioplasty and stent placement may not be sufficient for devices with longer intracoronary dwell times such as brachytherapy catheters. In light of current evidence, activated clotting times should be targeted in the 200- to 250-second range during elective PCI and in the 250- to 300-second range when intervening on a higher-risk lesion, such as one with an angiographically visible thrombus or in patients presenting with an acute coronary syndrome (ACS).Low-dose enoxaparin sodium is an attractive antithrombin strategy in PCI because it is intrinsically adjusted for renal function, age, and concomitant glycoprotein (GP) IIb/IIIa antagonist use. Other low-molecular weight heparins have also been studied as adjunctive anticoagulants during cardiac catheterization. For example, in pilot studies, dalteparin sodium was shown to have a good safety profile when used alone or in combination with abciximab during PCI.A wealth of data supports the use of a GP IIb/IIIa antagonist in patients presenting with ACS, especially those with high-risk features such as elevated cardiac markers; the systematic use of GP IIb/IIIa inhibitors in this population is therefore encouraged. Overall, the use of GP IIb/IIIa inhibitors reduces the incidence of thrombotic complications following PCI, is associated with a mortality benefit, but has no impact on the risk of restenosis.

Integrating antithrombin and antiplatelet therapies with early invasive management for non-ST-segment elevation acute coronary syndromes.

Non-ST-segment elevation acute coronary syndromes are a dramatic manifestation of coronary artery disease. Multiple clinical trials have shown that early cardiac catheterization improves clinical outcomes in patients with non-ST-segment elevation acute coronary syndromes. Many antithrombotic agents effectively manage unstable coronary syndromes and serve as adjuncts to percutaneous coronary intervention. Yet, the growing number of pharmacologic agents makes early management of non-ST-segment elevation acute coronary syndromes increasingly complex. We review the current evidence regarding the optimal integration of early antithrombotic and antiplatelet therapies with early coronary angiography and subsequent revascularization.

Optimal duration of eptifibatide infusion in percutaneous coronary intervention (an ESPRIT substudy).

Although randomized trials have clearly demonstrated the clinical efficacy with regimens of platelet glycoprotein IIb/IIIa antagonists that result in >80% inhibition of baseline platelet aggregation in percutaneous coronary intervention (PCI), there are no data available concerning the optimal duration of infusion of these agents. In an era when the length of hospitalization has a major impact on health care costs, the determination of the optimal duration of the infusion of these drugs after PCI is of great relevance. The investigators therefore sought to determine the optimal length of the infusion of eptifibatide after PCI by analyzing the outcomes of patients enrolled in the Enhanced Suppression of the Platelet IIb/IIIa Receptor With Integrilin Therapy trial who were randomized to treatment with eptifibatide.

Electrocardiography to define clinical status in primary pulmonary hypertension and pulmonary arterial hypertension secondary to collagen vascular disease.

STUDY OBJECTIVES: To determine the utility of the ECG for predicting clinical status in adults with primary pulmonary hypertension (PPH) or pulmonary arterial hypertension (PAH) secondary to collagen vascular disease. DESIGN: Retrospective study. SETTING: Outpatient clinic in a tertiary referral center. PATIENTS: Adult outpatients with PPH or PAH secondary to collagen vascular disease who underwent electrocardiography within 30 days of undergoing right-heart catheterization, echocardiography, and 6-min walk testing. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: The following measurements were recorded from each ECG: P-wave amplitude in lead II; mean frontal QRS axis; QRS duration; R-wave and S-wave deflections in leads I and V6; and the T-wave configurations in the precordial leads. These ECG variables were correlated with hemodynamic variables, RV size, and exercise capacity. Of the 61 patients included in this study, 56 (92%) were women. Eight of 61 patients (13%) had normal findings on ECGs. There was no significant difference in the demographics or hemodynamics when comparing groups with normal vs abnormal ECGs. All ECG parameters had no more than moderate correlation with hemodynamic variables, ventricular size measured by echocardiogram, and exercise capacity as measured by a 6-min walk. The best correlation was between mean the frontal QRS axis and cardiac index (r = -0.46). CONCLUSIONS: The ECG is an inadequate screening tool to rule out the presence of clinically relevant pulmonary hypertension, either primary or secondary to collagen vascular disease. The mean frontal QRS axis correlated best with the severity of hemodynamic impairment.

Left main coronary artery-to-pulmonary artery fistula with severe aneurysmal dilatation.

Coronary artery fistulas (CAF) are rare abnormalities that can be symptomatic or asymptomatic. Most drain into the right ventricle or pulmonary artery, though a variety of other drainage sites have been reported. We report the results of the surgical closure of a symptomatic left coronary-to-pulmonary artery fistula associated with a giant 10-cm aneurysm and discuss the management of coronary artery fistulas.

Contrast nephropathy : an evidence-based approach to prevention.

Contrast-induced nephropathy occurs in 2-10% of patients exposed to intravascular radiographic contrast agents and results in significant morbidity and mortality. Although the exact mechanism of this disorder has not been fully elucidated, contrast nephropathy is probably due to a combination of decreased renal medullary blood flow, resulting in medullary ischemia, and direct toxicity to renal tubules. Contrast nephropathy is most commonly defined as either a >25% increase or a >0.5 mg/dL rise in serum creatinine level within 48 hours of contrast medium exposure. Baseline characteristics associated with an increased risk for development of contrast nephropathy include the presence of baseline renal dysfunction, diabetes mellitus, congestive heart failure, volume depletion, and concomitant administration of nephrotoxic drugs. Many strategies have been investigated in an effort to prevent the occurrence of renal dysfunction following contrast media exposure. Intravenous hydration has been shown to significantly decrease the incidence of nephropathy in high-risk patients. However, trials of several prophylactic pharmacologic interventions have been mostly disappointing, including the administration of calcium channel antagonists, diuretics, dopamine, endothelin receptor antagonists and fenoldopam. The use of N-acetylcysteine has been shown in some trials to decrease the incidence of contrast nephropathy in patients with a baseline renal dysfunction, and should currently be strongly considered in this high-risk patient subgroup in addition to hydration. Our purpose is to review the contemporary literature regarding contrast-induced renal dysfunction and present an evidence-based approach for prevention of this complication.