Analysis of weekend effect on 30-day mortality among patients with acute myocardial infarction.

OBJECTIVES: Several publications have demonstrated increased 30-day mortality in patients admitted on Saturdays or Sundays compared with weekdays. We sought to determine whether this was true for two different cohorts of patients admitted with acute myocardial infarction (MI). METHODS AND RESULTS: Thirty-day mortality data were obtained for 3757 patients who had been admitted to the Belfast Health and Social Care Trust with acute MI between 2009 and 2015. They were subdivided into those presenting with ST elevation MI (n=2240) and non-ST elevation MI (n= 1517). We observed no excess 30-day mortality in those admitted over weekends. CONCLUSION: Excess mortality in patients admitted at weekends is not a universal finding. This may mean that that there are patient subgroups with proportionately greater weekend hazard and points to the need for more detailed understanding of the weekend effect.

A prospective intravascular ultrasound investigation of the necessity for and efficacy of postdilation beyond nominal diameter of 3 current generation DES platforms for the percutaneous treatment of the left main coronary artery.

OBJECTIVES: To define the size of the left mainstem coronary artery (LMS) in the Northern Irish population and investigate the clinical feasibility, safety, and efficacy of post dilation beyond nominal diameter of current generation Drug eluting stent (DES) when treating the LMS. BACKGROUND: There is no prospective data examining the need, feasibility, and safety of over-expansion of current generation DES beyond nominal diameter. METHODS: Patients with flow-limiting coronary atheroma requiring IVUS assessment of the LMS were recruited. Standardized measurements of the distal LMS were made. Subsequently, patients requiring post dilation of current generation DES within the LMS were entered into a PCI registry. RESULTS: Overall, 125 patients were recruited into the initial study. Mean cross-sectional area (CSA) of the distal LMS was 22.6 mm(2) (SD ± 5.4 mm(2) ). Mean maximal vessel diameter was 5.7 mm (SD ± 0.7 mm). Increasing plaque burden was associated with reduced CSA (P < 0.001). In 31 consecutive patients undergoing IVUS guided PCI of the LMS with 5.5 and 6.0 mm balloon catheters, mean maximal stent diameters were >5.0 mm with the Biomatrix Flex 9 crown and Promus Element Large vessel platforms. No intraprocedural complications occurred. Mean follow up was 13.4 months. Clinical restenosis rate was 3.2%, with 2 deaths unrelated to index procedure. CONCLUSIONS: The majority of patients with angiographic coronary atheroma have a mean LMS diameter of >4 mm indicating the requirement for post dilation beyond nominal diameter all of current generation DES in almost all patients when treating the LMS. This is achievable with current DES platforms with no intraprocedural complication. Clinical follow up indicates excellent short-term efficacy.

A classic diagnosis with a new 'spin'.

We describe a case of pericardial constriction following viral pericarditis and illustrate the use of cardiac magnetic resonance imaging in the diagnostic process. The advantages of cardiac magnetic resonance in the investigation of pericardial disease are briefly explained.

Prospective survey of serial troponin T requesting in an acute teaching hospital.

BACKGROUND: Requests for troponin T, a biomarker for myocardial infarction, may be sent in a variety of clinical situations. In most cases, a single sample 12 hours or more after symptom onset should be sufficient for diagnosis. We chose to investigate how troponin T testing is used in our hospital with emphasis on those who had serial rather than single troponin measurements during their hospital stay. METHODS: Prospective survey of 50 patients with serial troponin T requests out of a total of 321 patients who had troponin T levels measured during the same time period. RESULTS: The time of symptom onset could be clearly identified in 40/50 patients. In 22 of these the first troponin was taken prior to 12 hours after symptom onset. For the 18 patients whose first troponin was taken after 12 hours, the second result remained in the same category (normal or high) as the first in all cases. This was not the case for 3/10 patients whose first troponin was sent within 12 hours and was normal. Early troponin results rarely affected immediate patient management and did not inform decisions about fibrinolytic therapy. CONCLUSIONS: Serial troponin testing was most commonly due to a sample being sent within 12 hours of symptom onset or to unnecessary repetition of an appropriately timed sample. Patient management was rarely enhanced by early troponin testing.

Progressively increasing operative risk among patients referred for coronary artery bypass surgery.

OBJECTIVE: Advances in surgical, anaesthetic and percutaneous interventional techniques may have led to higher risk patients being referred for coronary artery bypass graft surgery (CABG). The purpose of this study was to compare the predicted mortality risk (EuroSCORE) of a contemporary cohort of patients referred for isolated elective CABG (2002) with that of a cohort referred five years previously (1997) and to examine temporal trends in patient demographics. METHODS: Records (n=2873) of weekly cardiac surgical referral meetings were examined and the age, sex, type of operation and surgical decision for every patient referred from 1997 to 2002 inclusive were recorded. Furthermore samples of patients referred in 1997 (n=111) and in 2002 (n=110) were chosen, and a complete EuroSCORE was calculated for each patient and compared between groups. RESULTS: In both 1997 and 2002 the median EuroSCORE among patients not accepted for surgery was significantly higher than those accepted (1997; 3 vs 2, p < 0.001. 2002; 5 vs. 2, p < 0.001). The median EuroSCORE of patients referred in 2002 was significantly higher than those referred in 1997 (3 vs. 2; p < 0.001). There was a progressive increase in median patient age throughout the study period and this accounted for the observed temporal increase in EuroSCORE. CONCLUSIONS: Predicted mortality risk among patients referred for coronary artery bypass surgery is increasing, mainly due to patient age at referral.

Evaluation of high-pressure retrograde coronary venous delivery of FGF-2 protein.

Delivery of angiogenic factors to ischemic myocardium remains a practical challenge. We evaluated the efficiency and efficacy of delivery of fibroblast growth factor-2 (FGF-2) protein via high-pressure retrograde injection into the anterior interventricular vein (AIV) in a porcine model of chronic myocardial ischemia. Labeled FGF-2 protein was delivered to the myocardium of three pigs via the AIV and the left anterior descending (LAD) coronary artery in three others. At 1 hr, the amount of protein in the left ventricle and the LAD region was quantified. Copper stents were implanted in the LAD of 25 pigs, resulting in chronic myocardial ischemia. At 4 weeks, microsphere-derived myocardial blood flow was assessed at rest and during pacing. In eight pigs (AIV FGF), FGF-2 protein (6 microg/kg) was delivered via high-pressure retrograde injection into the AIV. Six pigs (intracoronary FGF) received the same amount of FGF-2 by intracoronary delivery. Five pigs (AIV saline) received a placebo injection into the AIV and six pigs (control) served as controls. Four weeks later, myocardial blood flow was reassessed. At 1 hr, significantly more FGF remained in the left ventricle (1.3 vs. 0.82 microg; P < 0.04) and in the LAD region (1.2 vs. 0.64 microg; P = 0.03) after AIV compared to intracoronary delivery. Four weeks after treatment, resting LAD blood flow (normalized to right ventricular flow) improved slightly in the AIV FGF and intracoronary FGF arms (1.32-1.37 for both; P = 0.11), while it decreased significantly in the AIV saline (1.32-1.23; P = 0.02) and the control arms (1.32-1.19; P = 0.0004). Pacing LAD blood flow decreased significantly in the control arm (1.30-1.23; P < 0.05), but did not change significantly in the other three arms. High-pressure retrograde injection into the AIV may represent an efficient and effective means for delivering angiogenic factors to ischemic myocardium.

Flow-responsive remodeling after angioplasty is enhanced by high cholesterol diet. Prevention with pyrrolidine dithiocarbamate.

We examined the effects of high cholesterol diet and pyrrolidine dithiocarbamate (PDTC) on flow-dependent remodeling after angioplasty. After right common carotid balloon-injury, the right external carotid (low flow) or left common carotid artery were ligated (high flow) in rabbits fed normal diet, 1% cholesterol diet without or with the antioxidant PDTC for 7 days pre- and 7-28 days post-injury. Angiographic lumen diameter was significantly greater at 28 days in high flow than low flow normal diet animals, attributable on perfusion-fixed vessel morphometry to altered remodeling (area within the external elastic lamina: high flow 1.85+/-0.24 vs. low flow 1.31+/-0.04 mm(2), P<0.05) rather than differences in neointima formation or vessel tone. In animals on 1% cholesterol diet high flow remodeling was significantly enhanced (area within the external elastic lamina 3.13+/-0.17 mm(2), P<0.05 vs. high flow normal diet) but low flow inward remodeling was similar (area within the external elastic lamina 1.29+/-0.07 mm(2)). Mean Doppler flow velocities (initial/post-ligation/28 day follow-up, cm/s) had almost normalized in normal diet animals (high flow 30/49/35, low flow 32/9/26) but showed overcompensation in 1% cholesterol diet animals (high flow 32/49/22, low flow 30/11/25). PDTC therapy markedly attenuated remodeling (area within the external elastic lamina: high flow 2.20+/-0.18, and low flow 2.00+/-0.11 both P<0.05 vs. 1% cholesterol diet alone) and flow velocities only partially normalized (high flow 26/42/34, low flow 27/7/16). We conclude that hypercholesterolemia enhances and PDTC attenuates flow-dependent remodeling after angioplasty.

Effect of a change in gender on coronary arterial size: a longitudinal intravascular ultrasound study in transplanted hearts.

OBJECTIVES: We sought to document whether a physiologic change in gender has any effect on coronary arterial size. BACKGROUND: The coronary arteries are smaller in women, even after correction for body surface area (BSA). These differences may contribute to adverse clinical outcomes after coronary artery bypass graft surgery and myocardial infarction in women. In male and female transsexuals, pharmacologic doses of estrogens and androgens significantly influence vascular diameter. Thus, gender differences in the coronary vasculature may be a reflection of the hormonal environment. METHODS: In 86 patients who had undergone orthotopic heart transplantation, serial intravascular ultrasound studies of the proximal left anterior descending coronary artery (LAD) were analyzed. Changes in vessel area (VA) over the first or second post-transplant year were recorded, and comparisons were made between donor hearts that were transplanted in a patient of the same gender and those that were transplanted in a patient of the opposite gender. RESULTS: Vessel area of the proximal LAD increased over time in all patient groups. In hearts transplanted within the same gender and in male donor hearts transplanted to female recipients, the change was small and not significant. However, in hearts transplanted from female donors to male recipients, there was a substantial and highly significant increase in LAD VA (median 16.13 to 17.88 mm(2); p = 0.01). This increase was not explained by confounding due to changes in BSA or left ventricular wall thickness. CONCLUSIONS: This pattern of arterial remodeling early after heart transplantation supports a link between host gender and coronary arterial size.

Adjunctive platelet glycoprotein IIb/IIIa receptor inhibition with tirofiban before primary angioplasty improves angiographic outcomes: results of the TIrofiban Given in the Emergency Room before Primary Angioplasty (TIGER-PA) pilot trial.

BACKGROUND: Previous work has suggested that platelet glycoprotein IIb/IIIa receptor blockade may confer benefit in the treatment of acute myocardial infarction. The TIGER-PA pilot trial was a single-center randomized study to evaluate the safety, feasibility, and utility of early tirofiban administration before planned primary angioplasty in patients presenting with acute myocardial infarction. METHODS AND RESULTS: A total of 100 patients presenting with acute myocardial infarction were randomized to either early administration of tirofiban in the emergency room or later administration in the catheterization laboratory. The primary outcome measures were initial TIMI grade flow, corrected TIMI frame counts, and TIMI grade myocardial perfusion ("blush"). Thirty-day major adverse cardiac events were also assessed. Angiographic outcomes demonstrate a significant improvement in initial TIMI grade flow, corrected TIMI frame counts, and TIMI grade myocardial perfusion when patients are given tirofiban in the emergency room before primary angioplasty. The rate of 30-day major adverse cardiac events suggests that early administration may be beneficial. CONCLUSIONS: This pilot study suggests that early administration of tirofiban improves angiographic outcomes and is safe and feasible in patients undergoing primary angioplasty for acute myocardial infarction.