Radial Artery Occlusion After Transradial Access for Coronary Interventions

Background Transradial access (TRA) is a medical procedure primarily used for percutaneous coronary interventions (PCI) and cardiac catheterization. Based on the recently published Minimizing Adverse Haemorrhagic Events by Transradial Access Site and Systemic Implementation of AngioX (MATRIX) trial, TRA is being used more frequently than transfemoral access (TFA) since it has reduced rates of bleeding and fatality. A structural complication of TRA is radial artery occlusion (RAO), which may cause temporary pain to limit TRA in the future. Objective This study aimed to investigate the onset and risk factors of RAO following TRA for coronary interventions. Material and methods An observational study was conducted at Fauji Foundation Hospital in Peshawar, Pakistan. The study included 1,680 patients recruited between April 2021 to December 2023. Fifty-eight patients were lost to follow-up, while another 95 patients did not come for a visit within the study period. The final study, therefore, included 1,527 patients. Results The mean age of patients was 58.09 ± 8.07 years. Patients were divided into two age groups (greater or less than 60 years). Diagnostic angiograms were completed for 955 patients, while 572 also underwent PCI. The overall RAO onset was 81 (5.3%). There was a significantly higher RAO onset in patients over 60 years old (7.1 vs 3.8%, p = 0.003). Conclusion Overall, the risk of RAO is low following TRA. The risk of RAO is significantly higher in people aged over 60 years.

Effects of using primary percutaneous coronary interventions on the incidence of new-onset atrial fibrillation following an acute myocardial infarction

BACKGROUND

Acute ST-segment elevation myocardial infarction (STEMI) and new-onset atrial fibrillation (AF) are associated with increased risk of mortality.

HYPOTHESIS

This study aimed to determine the proportion of patients who go on to develop new-onset a AF after undergoing a primary or delayed percutaneous coronary intervention (PCI) for an acute STEMI and to explore possible risk factors.

METHODS

One hundred and fifty-four patients who underwent PCI after STEMI were included in the study. Patient characteristics, baseline blood tests and cardiac parameters, type of PCI, and incidence of new-onset AF within 3 months of PCI were recorded and analyzed.

RESULTS

Fifteen developed new-onset AF following the PCI, and 139 patients maintained a sinus rhythm. Univariate analysis showed significant differences between the two patient groups in terms of age, nature of the PCI (primary vs. delayed), left atrial diameter, and left ventricular diastolic dysfunction (p < .05). Age (odds ratio [OR] = 1.065, 95% confidence interval [CI]: 1.007-1.127, p < .05) and left atrial diameter (OR = 1.165, 95% CI: 1.008-1.347, p < .05), were independent predictors of new-onset AF after PCI. Primary PCI (OR = 0.232, 95% CI: 0.066-0.814, p < .05) was an independent protective factor.

CONCLUSION

Age and left atrial diameter were independent risk factors of new-onset AF in patients undergoing a PCI following an acute myocardial infarction, while primary PCI was a protective factor. This discovery can help reduce mortality rate, improve long-term prognosis, and provide a theoretical basis for the prevention of new-onset AF.

A Case of Post-Myocardial Infarction Ventricular Septal Rupture Complicated by Postoperative Septal Rupture

We present the case of a 60-year-old man who presented with a post-myocardial infarction ventricular septal rupture caused by a delayed presentation of myocardial infarction. Despite revascularization, hemodynamic stability, and a 10-day delay until operative management to allow for tissue healing, the patient experienced a fatal recurrent postoperative ventricular septal rupture. (Level of Difficulty: Beginner.).

Long-term cardiovascular outcomes and temporal trends in patients diagnosed with ANCA-associated vasculitis: a Danish nationwide registry study

OBJECTIVES

To examine long-term cardiovascular outcomes and temporal trends among patients with ANCA-associated vasculitis (AAV) using Danish nationwide registries.

METHODS

Using a cohort design, we examined patients with granulomatosis with polyangiitis (ICD-10: DM31.3) and microscopic polyangiitis (ICD-10: DM3.17) in Denmark from 1996-2018. Hazard ratios (HRs) of cardiovascular outcomes were compared between patients with AAV and age and gender-matched controls. Counterfactual G-estimation of HRs was performed to estimate 5-year absolute risks. Temporal trends were obtained by grouping cohorts into evenly distributed tertiles according to inclusion year.

RESULTS

A total of 2306 patients with AAV (median age: 62.9yrs, 52.6% male) were matched with 6918 controls. Median follow-up was 9.5yrs. Patients with AAV had a higher rate of ischaemic heart disease [HR 1.86 (1.62-2.15)], myocardial infarction [HR 1.62 (1.26-2.09)], coronary angiogram [HR 1.64 (1.37-1.96)], percutaneous coronary intervention [HR 1.56 (1.17-2.07)] and ventricular arrhythmias/implantable-cardioverter-defibrillator (ICD)-implantations [HR 2.04 (1.16-3.57)]. Similarly, an increased rate of heart failure [HR 2.12 (1.77-2.54)], deep vein thrombosis [HR 3.13 (2.43-4.05)], pulmonary embolism [HR 4.04 (3.07-5.32)], atrial fibrillation [HR 2.08 (1.82-2.39)], ischaemic stroke [HR 1.58 (1.31-1.90)] and in-hospital cardiac arrest [HR 2.27 (1.49-3.48)] was observed. The 5-year risk of all outcomes were significantly higher (excluding ventricular arrhythmia/ICD-implantations). For temporal trends among patients with AAV, a decreased 3-year risk of cardiovascular mortality was observed over time.

CONCLUSIONS

Patients with AAV are at increased risk of heart failure, atrial-/ventricular arrhythmias, venous thrombotic events, ischaemic stroke and myocardial infarction. Furthermore, patients with AAV were more frequently examined with coronary procedures and underwent more coronary revascularizations. No temporal changes in ischaemic cardiovascular outcomes were observed, albeit the cardiovascular mortality has decreased over time.

Feasibility of distal transradial access for coronary angiography and percutaneous coronary intervention: an observational and prospective study in a Latin-American Centre

BACKGROUND

Distal transradial access (dTRA) as a refinement of the conventional transradial access (TRA) has advantages in terms of risk of radial artery occlusion (RAO). In order to evaluate the real-world feasibility and safety of dTRA as the default access site for routine coronary angiography (CAG) and percutaneous coronary intervention (PCI) in a Latin-American centre, this prospective observational registry was conducted.

METHODS

Consecutive patients with a prior assessment for CAG and/or PCI were enrolled in this single-centre prospective registry from October 2018 to March 2019. The primary endpoints were the success rate of CAG and PCI. Secondary endpoints included the success rate of puncture of the distal radial artery, complications at the puncture site and puncture time.

RESULTS

The success rates of CAG and PCI were 100% (155/155) and 97% (69/71), respectively. Puncture time and fluoroscopic time were 52 ± 19 seconds and 16.3 ± 35.4 minutes, respectively. Haemostasis time was 142 ± 45 min. A total of 19 (12.5%) puncture site complications occurred, including 18 (11.6%) minor haematomas and one (0.6%) arterial perforation, in which the artery was patent at the one-month follow-up. Five patients complained of left thumb numbness at a one-month follow-up. No distal radial artery occlusion, pseudoaneurysm, or arteriovenous fistula occurred.

CONCLUSIONS

The success and complication rates of ldTRA support the feasibility and safety of this procedure using the appropriate materials in previously selected patients.

ST-Elevation Myocardial Infarction Among Septic Shock and Coronary Interventions: A National Emergency Database Study

OBJECTIVE

To study coronary interventions and mortality among patients with ST-elevated myocardial infarction (STEMI) who were admitted with septic shock.

METHODS

Data from the national emergency department sample (NEDS) that constitutes 20% sample of hospital-owned emergency departments in the United States was analyzed for the septic shock related visits from 2016 to 2018. Septic shock was defined by the ICD codes.

RESULTS

Out of 1 375 507 adult septic shock patients, 521 300 had a primary diagnosis of septic shock (mean age 67.41±15.67 years, 51.1% females) in the national emergency database for the years 2016 to 2018. Of these patients, 2768 (0.53%) had STEMI recorded during the hospitalization. Mortality rates for STEMI patients were higher than patients without STEMI (52.3% vs 23.5%). Mortality rates improved with PCI among STEMI patients (43.8% vs 56.2%). Coronary angiography was performed among 16% of patients of which percutaneous coronary intervention (PCI) rates were 7.7% among patients with STEMI septic shock. PCI numerically improved mortality, however, had no significant difference than patients without PCI on multivariate logistic regression and univariate logistic regression post coarsened exact matching of baseline characteristics among STEMI patients. Among the predictors, STEMI was a significant predictor of mortality in septic shock patients (OR 2.87, 95% CI 2.37-3.49; P<.001). Age, peripheral vascular disease, were predominant predictors of mortality in STEMI with septic shock subgroup (P <.001). Pneumonia was the predominant underlying infection among STEMI (36.4%) and without STEMI group (29.5%).

CONCLUSION

STEMI complicating septic shock worsens mortality. PCI and coronary angiography numerically improved mortality, however, had no significant difference from patients without PCI. More research will be needed to improve mortality in such a critically ill subgroup of patients.

Access-site Complications of the Transradial Approach: Rare But Still There

In the past decade, the Transradial Approach (TRA) has constantly gained ground among interventional cardiologists. TRA’s anatomical advantages, in addition to patients’ acceptance and financial benefits, due to rapid patient mobilization and shorter hospital stay, made it the default approach in most catheterization laboratories.

Access-site complications of TRA are rare and usually of little clinical impact, thus, they are often overlooked and underdiagnosed. Radial Artery Occlusion (RAO) is the most common, followed by radial artery spasm, perforation, hemorrhagic complications, pseudoaneurysm, arterio-venous fistula, and even rarer complications, such as nerve injury, sterile granuloma, eversion endarterectomy or skin necrosis. Most of them are conservatively treated, but rarely, surgical treatment may be needed and late diagnosis may lead to life-threatening situations, such as hand ischemia or compartment syndrome and tissue loss. Additionally, some complications may eventually lead to TRA failure and switch to a different approach.

On the other hand, it is the opinion of the authors that non-occlusive radial artery injury, commonly included in TRA’s complications in the literature, should be regarded more as an anticipated functional and anatomical cascade, following radial artery puncture and sheath insertion.

Coronary revascularization in patients with stable coronary disease and diabetes mellitus

PURPOSE OF STUDY

Diabetes mellitus accelerates the development of atherosclerosis. Patients with diabetes mellitus have higher incidence and mortality rates from cardiovascular disease and undergo a disproportionately higher number of coronary interventions compared to the general population. Proper selection of treatment modalities is thus paramount. Treatment strategies include medical management and interventional approaches including coronary artery bypass graft (CABG) surgery and percutaneous coronary interventions (PCI). The purpose of this review is to assimilate emerging evidence comparing CABG to PCI in patients with diabetes and present an outlook on the latest advances in percutaneous interventions, in addition to the optimal medical therapies in patients with diabetes.

KEY METHODS

A systematic search of PubMed, Web of Science and EMBASE was performed to identify prospective, randomized trials comparing outcomes of CABG and PCI, and also PCI with different generations of stents used in patients with diabetes. Additional review of bibliography of selected studies was also performed.

MAIN CONCLUSIONS

Most of the trials discussed above demonstrate a survival advantage of CABG over PCI in patients with diabetes. However, recent advances in PCI technology are starting to challenge this narrative. Superior stent designs, use of specific drug-eluting stents, image-guided stent deployment, and the use of contemporary antiplatelet and lipid-lowering therapies are continuing to improve the PCI outcomes. Prospective data for such emerging interventional technologies in diabetes is however lacking currently and is the need of the hour.

Endpoint selection for noninferiority percutaneous coronary intervention trials: a methodological description

Background:

The objective of this review is to provide a practical update on endpoint selection for noninferiority (NI) studies in percutaneous coronary intervention studies.

Methods:

A PubMed search was conducted for predefined terms to explore the use of NI designs and intrapatient comparisons to determine their current importance. Sample size calculations for the most frequently used endpoints with NI hypotheses were done to increase statistical awareness.

Results:

Reported NI trials, with the most frequently chosen clinical endpoint of major adverse cardiac events (MACE), had NI margins ranging from 1.66% to 5.00%, resulting in patient populations of 400–1500 per treatment group. Clinical study endpoints comprising of MACE complemented with rates of bleeding complications and stent thrombosis (ST) are suggested to conduct a statistically and clinically meaningful NI trial. Study designs with surrogate endpoints amenable to intrapatient randomizations, are a very attractive option to reduce the number of necessary patients by about half. Comparative clinical endpoint studies with MACE and ST/bleeding rates to study a shortened dual antiplatelet therapy (DAPT) in coronary stent trials are feasible, whereas ST as the sole primary endpoint is not useful.

Conclusions:

Expanded composite clinical endpoints (MACE complemented by ST and bleeding rates and intrapatient randomization for selected surrogate endpoints) may be suitable tools to meet future needs in device approval, recertification and reimbursement.

QFR Predicts the Incidence of Long-Term Adverse Events in Patients with Suspected CAD: Feasibility and Reproducibility of the Method

AIMS

We evaluate feasibility and reproducibility of post hoc quantitative flow ratio (QFR) measurements and their prognostic predictive power during long-term follow-up.

METHODS AND RESULTS

Between 2010 and 2012, 167 patients without angiographic evidence of significant stenoses were enrolled in a prospective registry. Of these patients, 96% presented 7 years follow-up data. QFR was measured post hoc by three certified investigators. QFR analysis was feasible in 71% of left anterior descending (LAD), 72% of left circumflex (LCX), and 61% of right (RCA) coronaries for a total of 350 measurements repeated in triplicate. Coefficients of variation were 2.1% for RCA and LCX, and 2.8% for the LAD (quartile coefficients of dispersion respectively 1.5, 1.4, and 1.3). QFR ≤0.80 was recorded in 25 patients (27 vessels, in 74% of the cases LAD). A total of 86 major adverse cardiovascular and cerebrovascular events were observed in 76 patients. QFR ≤0.80 in at least one of the three vessels was the strongest predictor of events (HR 3.14, 95%CI 1.78-5.54, p = 0.0001). This association was maintained in several sensitivity analyses.

CONCLUSIONS

QFR reproducibility is acceptable, even when analysis is performed post hoc. A pathological QFR is not rare in patients without angiographic evidence of significant stenosis and is a predictor of incident events during long-term follow-up.

CONDENSED ABSTRACT

In a post hoc analysis of 167 patients without evidence of angiographic significant stenosis, the presence of QFR value ≤0.80 in at least one of the three coronary vessels showed to be the strongest predictor of major adverse cardiovascular and cerebrovascular events during long-term follow-up. QFR reproducibility have been shown to be acceptable among experienced operators.

Complete Revascularization During Primary Percutaneous Coronary Intervention Reduces Death and Myocardial Infarction in Patients With Multivessel Disease: Meta-Analysis and Meta-Regression of Randomized Trials. JACC Cardiovasc Interv. 2018;11:833-843. [PMID: 29747913 DOI: 10.1016/j.jcin.2018.02.028]

OBJECTIVES

The aim of this study was to compare complete revascularization with a culprit-only strategy in patients presenting with ST-segment elevation myocardial infarction (MI) and multivessel disease by a meta-analysis of randomized trials.

BACKGROUND

Although several trials have compared complete with culprit-only revascularization in ST-segment elevation MI, it remains unclear whether complete revascularization may lead to improvement in hard endpoints (death and MI).

METHODS

Randomized trials comparing complete revascularization with culprit-only revascularization in patients with ST-segment elevation MI without cardiogenic shock were identified by a systematic search of published research. Random-effects meta-analysis was performed, comparing clinical outcomes in the 2 groups.

RESULTS

Eleven trials were identified, including a total of 3,561 patients. Compared with a culprit-only strategy, complete revascularization significantly reduced risk for death or MI (relative risk [RR]: 0.76; 95% confidence interval [CI]: 0.58 to 0.99; p = 0.04). Meta-regression showed that performing complete revascularization at the time of primary percutaneous coronary intervention (PCI) was associated with better outcomes (p = 0.016). The 6 trials performing complete revascularization during primary PCI (immediate revascularization) were associated with a significant reduction in risk for both total mortality (RR: 0.62; 95% CI: 0.39 to 0.97; p = 0.03) and MI (RR: 0.40; 95% CI: 0.25 to 0.66; p < 0.001), whereas the 5 trials performing only staged revascularization did not show any significant benefit in either total mortality (RR: 1.02; 95% CI: 0.65 to 1.62; p = 0.87) or MI (RR: 1.04; 95% CI: 0.48 to 1.68; p = 0.86).

CONCLUSIONS

When feasible, complete revascularization with PCI can significantly reduce the combined endpoint of death and MI. Complete revascularization performed during primary PCI was also associated with significant reductions in both total mortality and MI, whereas staged revascularization did not improve these outcomes.

Acute coronary artery obstruction following surgical repair of congenital heart disease

OBJECTIVES

Acute coronary artery obstruction is a rare complication of congenital heart disease surgery but imposes a high burden of morbidity and mortality. Previous case series have described episodes in specific congenital heart lesions or surgical repairs but have not examined the complication in all-comers to congenital heart surgery. We hypothesize that shorter time from a clinically recognized postoperative sentinel event suggestive of coronary ischemia to diagnosis of coronary obstruction is associated with improved clinical outcomes.

METHODS

This was a single-center, retrospective review of patients diagnosed with acute coronary artery obstruction by angiography following surgical repair of congenital heart disease between January 2000 and June 2016.

RESULTS

In total, 34 patients were identified. The most common procedures associated with coronary artery obstruction were the Norwood procedure, arterial switch operation, and aortic valve repair/replacement. In total, 79% required mechanical circulatory support, 41% died, and 27% were listed for heart transplant. Patients who died or were listed for heart transplant had longer median sentinel-event-to-cardiac-catheterization time (28 [6-168] hours vs 10 [3-56] hours, P = .001), and longer median sentinel-event-to-intervention time (32 [11-350] hours vs 13 [5-59] hours, P = .003). Patients with hypoplastic left heart syndrome were at greater risk of death or transplant listing (odds ratio, 9.23, P = .03).

CONCLUSIONS

Time from clinically relevant postoperative sentinel event to diagnosis of coronary artery obstruction by angiography was associated with transplant-listing-free survival. Clinicians should maintain a high index of suspicion for coronary obstruction and consider early catheterization and coronary angiography for patients in whom post-operative coronary compromise is suspected.

Distal transradial access as default approach for coronary angiography and interventions

Background

Distal transradial access (dTRA) as a refinement of the conventional transradial access has advantages in terms of patient and operator comfort and risk of radial artery (RA) occlusion. RA preservation with this new technique could be a relevant issue in patients requiring its future use. In turn, one relevant drawback is the more challenging puncture of a smaller artery. In order to evaluate the real world feasibility and safety of both right (rdTRA) and left (ldTRA) distal transradial access as default access site for routine coronary angiography (CAG) and percutaneous coronary intervention (PCI), this prospective observational registry was conducted.

Methods

From February to July 2019, 435 consecutive patients underwent CAG and/or PCI (620 procedures at all, by two experienced transradial operators) through rdTRA or ldTRA.

Results

Mean patient age was 62.4 years old. Most were male (66.0%). The majority (49.4%) of patients had an acute coronary syndrome; overall, 15.2% with ST-elevation acute myocardial infarction (STEMI). Distal RA was successfully punctured in all patients, always without ultrasound guidance, with puncture and sheath insertion at until 2 attempts in the vast majority of patients. We had only 3.0% access site crossovers (successful arterial puncture but failed sheath insertion), mainly performed via the contralateral dTRA (53.8%). Successful dTRA sheath insertion was then achieved in 98.6% of all 435 patients. Redo ipsilateral dTRA was performed in 2.5% of patients. Distal and proximal RA pulses were palpable in all patients at hospital discharge. No major adverse cardiac and cerebrovascular events and no major complications were recorded.

Conclusions

dTRA as default approach for routine CAG and/or PCI by experienced transradial operators appears to be safe and feasible. Further randomized and larger trials are still needed to assure the clinical benefits and the safety of this new technique.

Very distal transradial approach (VITRO) for coronary interventions

Introduction

Radial access is a standard approach for coronary interventions. However, it carries some risk of local or long-term complications such as hematoma or radial artery occlusion.

Aim

To assess the feasibility of a very distal left and right transradial approach (VITRO) for coronary interventions.

Material and methods

Three hundred and twenty consecutive patients were submitted to diagnostic or therapeutic coronary interventions. In 102 patients the distal radial artery was not palpable or the pulse was too weak. In 218 selected patients (142 male, 76 female, age: 69 ±11 years) we decided to perform a distal transradial approach.

Results

The VITRO access was suitable in 195 patients with a success rate of 89.4%. In 9 patients arterial puncture failed, while in 14 others despite successful arterial puncture the wire could not be advanced towards the forearm part of the radial artery. Not only elective diagnostic angiographies were performed with VITRO but also urgent ad hoc coronary interventions in subjects with unstable angina or NSTEMI (48 subjects; 24.3%). Moreover, this very distal approach allowed 11 rotablations and 11 FFR/iFR examinations to be performed in 22 patients. No major bleeding, requiring prolonged hospital stay, surgery or transfusion occurred. One patient on oral anticoagulation with DAPT had conservatively managed minor forearm bleeding.

Conclusions

Very distal radial artery access is feasible, safe and comfortable in 60% of patients referred for elective or urgent coronary arteries angiography, or coronary interventions.

Outcomes of in-hospital treatment of cardiac patients who survived cardiac arrest and experienced coronary angiography

Introduction

As coronary artery disease is the most frequent cause of cardiac arrest, early invasive strategies may be beneficial for such patients. This study analyses the impact of in-hospital treatment on short-term outcomes of out-of-hospital cardiac arrest (OHCA) survivors.

Material and methods

Patients admitted to the Cardiac Intensive Care Unit of our hospital within 2-year period were prospectively included in the study.

Results

One hundred thirty-one patients were included in the study, which showed that in-hospital mortality increases uniformly with the severity of the coronary artery lesion (p = 0.044), but an effect of revascularization on number of deaths was not observed (p = 0.64). The presence of coma (p = 0.005) and the combination of male sex and age above 60-year as 2.2-fold (p = 0.048) increasing in-hospital mortality were found. The highest mortality rate occurred during the first 3 days and the death rate of the patients who survived this period is low. We found reduced left ventricular ejection fraction (OR = 6.54; 95% CI: 1.98-21.63; p = 0.002), non-ventricular fibrillation initial rhythm (OR = 2.94; 95% CI: 1.25-6.90; p = 0.014), unconscious at admission (OR = 6.46; 95% CI: 1.96-21.24; p = 0.002) and post-resuscitation coma (OR = 6.00; 95% CI: 2.63-13.66; p < 0.001) or encephalopathy (OR = 2.71; 95% CI: 1.9-6.72; p = 0.031) to be significant prognostic factors for higher in-hospital mortality rate.

Conclusions

We recommend immediate coronary interventions for all survivors of OHCA regardless of their state of consciousness and absence of ischaemic changes on ECG. Early intensive treatment for OHCA patients is indispensable, as the highest mortality rate is within the first 3 days after an event.

Cellular postconditioning: allogeneic cardiosphere-derived cells reduce infarct size and attenuate microvascular obstruction when administered after reperfusion in pigs with acute myocardial infarction

BACKGROUND

Intracoronary delivery of cardiosphere-derived cells (CDCs) has been demonstrated to be safe and effective in porcine and human chronic myocardial infarction. However, intracoronary delivery of CDCs after reperfusion in acute myocardial infarction has never been assessed in a clinically-relevant large animal model. We tested CDCs as adjunctive therapy to reperfusion in a porcine model of myocardial infarction.

METHODS AND RESULTS

First, escalating doses (5, 7.5, and 10 million cells) of allogeneic CDCs were administered intracoronary 30 minutes after reperfusion. Forty-eight hours later, left ventriculography was performed and animals euthanized to measure area at risk, infarct size (IS), and microvascular obstruction. Second, identical end points were measured in a pivotal study of minipigs (n=14) that received 8.5 to 9 million allogeneic CDCs, placebo solution, or sham. Multiple indicators of cardioprotection were observed with 7.5 and 10 million allogeneic CDCs, but not 5 million CDCs, relative to control. In the pivotal study, IS, microvascular obstruction, cardiomyocyte apoptosis, and adverse left ventricular remodeling were all smaller in the CDC group than in sham or placebo groups. In addition, serum troponin I level at 24 hours was lower after CDC infusion than that in the placebo or sham groups, consistent with the histologically-demonstrated reduction in IS.

CONCLUSIONS

Intracoronary delivery of allogeneic CDCs is safe, feasible, and effective in cardioprotection, reducing IS, preventing microvascular obstruction, and attenuating adverse acute remodeling. This novel cardioprotective effect, which we call cellular postconditioning, differs from previous strategies to reduce IS in that it works even when initiated with significant delay after reflow.

MRI demonstrates a decrease in myocardial infarct healing and increase in compensatory ventricular hypertrophy following mechanical microvascular obstruction

PURPOSE

To provide direct evidence that mechanical obstruction of microvessels inhibits infarct resorption (healing) and enhances left ventricular (LV) remodeling using MRI.

MATERIALS AND METHODS

Animals (n = 20 pigs) served as controls (group I) or were subjected to either 90 min left anterior descending (LAD) coronary artery occlusion/reperfusion (group II) or 90 min LAD occlusion/ microemboli delivery/reperfusion (group III). MRI (cine and delayed contrast enhanced MRI, DE-MRI) was performed at 3 days and 5 weeks after interventions and used for assessing LV function, mass, and extent of myocardial damage and microvascular obstruction (MVO) using semi-automated threshold method.

RESULTS

Persistent MVO in the core of contiguous infarct was larger and more frequent (n = 8/8) in group III than group II (4/8) on DE-MRI at 3 days. Furthermore, patchy microinfarct, as a result of microembolization, was visible as hyperenhanced zone at the borders of the contiguous infarct. The reduction in ejection fraction and increase in LV volumes on cine MRI were greater in group III than group II at 3 days and 5 weeks, which may be attributed to the slow infarct resorption, MVO extents and patchy microinfarct at the borders.

CONCLUSION

This MRI study illustrates the recently raised conjecture that MVO delays/inhibits infarct resorption (healing), accentuates LV hypertrophy and pathological remodeling.

Coronary computed tomography angiography in planning of percutaneous coronary interventions in bifurcation lesions - study design and rationale

Percutaneous treatment of coronary bifurcations is a complex issue due to numerous possible techniques and high risk of complications. Because of increasing interest in non-invasive imaging in interventional cardiology and growing quality of obtained images, we designed a prospective, randomized, single-blinded trial to evaluate the role of coronary computed tomography angiography (CCTA) in the planning of percutaneous coronary interventions (PCI) of bifurcation lesions. Eighty eligible patients scheduled for PCI of bifurcations in stable coronary artery disease will undergo additional CCTA examination and will be randomized 1: 1 to either planning of PCI using angiography and CCTA or to PCI planning with use of angiography alone. Primary endpoints will include PCI strategy (one or two stents), technique, size of implanted stents and direct angiographic effect of the procedure. Immediate PCI effect measured with intravascular ultrasound (IVUS) and the effect on fractional flow reserve (FFR) in the side branch (in a subgroup of patients), as well as plaque morphology assessed in CCTA, patient radiation exposure and amount of contrast will be compared in secondary analysis. The study is intended to clarify the influence of CCTA analysis on the technique and direct effect of PCI of bifurcations and to provide evidence on the relevance of performing a CCTA scan prior to PCI of bifurcation lesions.

Estrogen-induced improvement in coronary flow responses during atrial pacing in relation to endothelin-1 levels in postmenopausal women without coronary disease

BACKGROUND

The cardioprotective role of hormonal replacement therapy remains in doubt, but interest is increasing in the vascular effects of estrogens especially in coronary circulation.

METHODS

Coronary blood flow (CBF) was measured in 24 postmenopausal women (age 55+/-3 years), whose coronary arteries appeared angiographically normal, during incremental atrial pacing (AP) before and 20 minutes after intracoronary administration of either 75 ng/mL 17-beta estradiol (treated group, n=18) or 0.9% saline (controls, n=6).

RESULTS

Before estrogen, no differences in the coronary vasomotor responses at AP between the two groups (p=NS) could be detected. After estrogen, in the treated group, at the peak of the second AP, the coronary artery diameter decreased by 0.17 mm (p<0.005) while the CBF increased by 61 mL/min (p<0.05). These changes differed significantly from those observed at the peak of first AP (p<0.001 for both cases). In contrast, in the control group no such changes were observed. The endothelin-1 (ET-1) levels in the coronary sinus were significantly reduced after estrogen infusion, which was negatively correlated with the degree of coronary artery constriction (r= -0.40, p=0.03) and positively correlated with the increase in CBF (r=0.54, p=0.01).

CONCLUSIONS

In postmenopausal women without coronary artery disease, the intracoronary estrogen infusion mediates a greater increase in CBF and is positively correlated with the reduction of the coronary sinus ET-1 levels at the peak of AP.