Coronary Recanalization Research Articles

E0423 The research about the short-time effects of preinfraction angina in patients complicated with acute myocardial infraction and treated by primary percutaneous coronary intervention

ObjectiveTo evaluate the short-time effects, angiographic characteristics, and the clinical outcome of preinfarction angina in patients with first acute myocardial infarction (AMI) after emergency primary percutaneous coronary intervention (PCI). And...

Prevention and treatment of no-reflow

No-reflow phenomenon occurs frequently during primary percutaneous coronary intervention for ST-segment elevation myocardial infarction and it has a strong negative impact on outcome. Prevention of no-reflow has to be defined as any attempt to prevent its occurrence prior to or during the recanalization procedure. Strategy of prevention may be pharmacological or device based. Among drugs, abciximab is indicated by European Society of Cardiology (ESC) guidelines for prevention of no-reflow (class of recommendation IIa and level of evidence B). Among devices used for preventing no-reflow, manual thrombus aspiration only has been associated with a reduction of no-reflow and lower mortality at follow-up and is currently indicated in the ESC guidelines (class IIa of recommendation and level B of evidence). Treatment of no-reflow has to be defined as any attempt to treat its occurrence after coronary recanalization. Strategy of treatment may be pharmacological or device based. Adenosine and verapamil are indicated by ESC guidelines for treatment of no-reflow (class of recommendation IIb and level of evidence B and C, respectively). Serial assessment of myocardial perfusion showed that in up to 50% of patients no-reflow is spontaneously reversible. This finding may open new scenarios, as mechanisms of reversibility may become future therapeutic targets.

Efficacy and Safety of Drug-Eluting Stents in Chronic Total Coronary Occlusion Recanalization: A Systematic Review and Meta-Analysis

The aim of this study was to compare the efficacy and safety of drug-eluting stent (DES) and bare-metal stent (BMS) use in chronic total occlusion (CTO) recanalization. The long-term effectiveness and safety of DES use in CTO recanalization are unclear, and performance of randomized clinical trials in the field is complex. Major electronic information sources were explored for articles comparing outcomes with DES and BMS use among patients with CTO. Assessed clinical outcomes were death, myocardial infarction, target vessel revascularization, major adverse cardiac events, and stent thrombosis; angiographic outcomes were stent restenosis and stent reocclusion. Fourteen comparative studies were identified (a total of 4,394 patients). When compared with BMS, DES significantly reduced risk of major adverse cardiac events (relative risk [RR]: 0.45, 95% confidence interval [CI]: 0.34 to 0.60, p < 0.001) and TVR (RR: 0.40, 95% CI: 0.28 to 0.58, p < 0.001) without increasing death (RR: 0.87, 95% CI: 0.66 to 1.16, p = 0.88) or myocardial infarction (RR: 0.89, 95% CI: 0.54 to 1.46, p = 0.80). This benefit was sustained at >/=3 years of follow-up. Lower RRs for restenosis (RR: 0.25, 95% CI: 0.16 to 0.41, p < 0.001) and stent reocclusion (RR: 0.30, 95% CI: 0.18 to 0.49, p < 0.001) were also observed in the DES group. A strong trend toward a higher rate of stent thrombosis was documented in DES-treated patients (RR: 2.79, 95% CI: 0.98 to 7.97, p = 0.06). DES use in CTO recanalization is associated with significantly fewer major adverse cardiac events and fewer occurrences of target vessel revascularization, restenosis, and stent reocclusion than with BMS. Although a statistical trend toward a higher risk of stent thrombosis was observed, the use of DES in this context seems to be safe, with an overall benefit sustained in the long term.

Contemporary principles of coronary chronic total occlusion recanalization

Successful recanalization and percutaneous revascularization of coronary arteries with chronic total occlusion (CTO) is one of the "last frontiers" in coronary interventions. Conquering this objective may enable complete percutaneous revascularization in an increasing number of patients. Revascularization of CTOs carries multiple theoretical advantages such as improvement in wall motion abnormalities and left ventricular function, and ultimately, increased long-term survival. In the long term, when coronary disease progresses, having an open artery may increase the tolerance to future coronary events. The contemporary principles of the recanalization technique are reviewed.

Adjunctive treatment with ticagrelor, but not clopidogrel, added to tPA enables sustained coronary artery recanalisation with recovery of myocardium perfusion in a canine coronary thrombosis model

Reperfusion therapy for myocardial infarction is limited by significant re-occlusion rates and less-than-optimal myocardial tissue perfusion. It was the objective of this study to assess and compare the effect of ticagrelor, the first reversibly binding oral P2Y12 receptor antagonist, with that of clopidogrel, in conjunction with thrombolytic therapy, on platelet aggregation, thrombus formation, and myocardial perfusion in a canine model. Thrombus formation was induced by electrolytic injury and blood flow was measured with a Doppler ultrasonic flowmeter. All animals received tissue plasminogen activator (tPA) (1 mg/kg over 20 min); 10 animals received clopidogrel (10 mg/kg IV bolus over 5 min), 10 animals received ticagrelor initiated with a 1-min bolus (75 microg/kg/min), followed by continuous infusion (10 microg/kg/min) for 2 h, and 10 animals received IV saline. Re-occlusion rate and cyclic flow variation decreased with ticagrelor compared to saline groups (p<0.05). Adenosine phosphate (ADP)-induced platelet aggregation decreased with ticagrelor (1.9% +/- 2.67) and clopidogrel (1.11% +/- 2.0) vs. saline (26.3% +/- 23.5, p<0.05) at the end of adjunctive therapy. Bleeding time increased in the clopidogrel compared to the ticagrelor group (p=0.01). Infarct size was reduced with ticagrelor compared to the clopidogrel and saline groups (p<0.05). Blood flow remained significantly below baseline values at 20 min after tPA administration in the saline and clopidogrel groups but not in the ticagrelor group. In conclusion, in a dog coronary thrombosis model, ticagrelor blocks ADP-induced platelet activation and aggregation; prevents platelet-mediated thrombosis; prolongs reperfusion time and reduces re-occlusion and cyclic flow variation; and significantly decreases infarct size and rapidly restores myocardial tissue perfusion.

Impact of Left Ventricular Ejection Fraction on Clinical Outcomes Over Five Years After Infarct-Related Coronary Artery Recanalization (from the Occluded Artery Trial [OAT

In the Occluded Artery Trial (OAT), percutaneous coronary intervention (PCI) of an infarct-related artery on days 3 to 28 after acute myocardial infarction was of no benefit compared to medical therapy alone. The present analysis was conducted to determine whether PCI might provide benefit to the subgroup of higher risk patients with a depressed ejection fraction (EF). Of 2,185 analyzed patients (age 58.6 +/- 11.0 years) with infarct-related artery occlusion on days 3 to 28 after acute myocardial infarction in the Occluded Artery Trial, 1,094 were assigned to PCI and 1,091 to medical therapy. The primary end point was a composite of death, reinfarction, and New York Heart Association class IV heart failure. The outcomes were analyzed by EF (first tertile, EF < or =44%, vs second and third tertiles combined, EF >44%). Interaction of the treatment effect with EF on the study outcomes were examined using the Cox survival model. The 5-year rates of the primary end point (death, reinfarction, or New York Heart Association class IV heart failure) were not different in either subgroup (PCI vs medical therapy, hazard ratio 1.25, 99% confidence interval 0.83 to 1.88, for EF < or =44%; hazard ratio 0.98, 99% confidence interval 0.64 to 1.50, for EF >44%). However, in patients with an EF >44%, PCI reduced the rate of subsequent revascularization (p = 0.004, interaction p = 0.05). In conclusion, optimal medical therapy remains the overall treatment of choice for stable patients with a persistent total occlusion of the infarct-related artery after acute myocardial infarction, irrespective of the baseline EF. In patients with normal or moderately impaired left ventricular contractility, PCI reduced the need for subsequent revascularization but did not otherwise improve outcomes.

Abstract 4862: ST-Segment Depression in Lead aVR: A Useful Predictor of Impaired Myocardial Reperfusion in Patients With Anterolateral ST-Segment Elevation Acute Myocardial Infarction

Background: ST-segment depression in lead aVR during ST-segment elevation acute myocardial infarction (STEMI) theoretically represents a reciprocal change in response to an opposite vector resulting from ST-segment elevation in the apical and inferolateral walls. We hypothesized that ST-segment depression in lead aVR during anterolateral STEMI is associated with less successful myocardial reperfusion, because of more extensive area at risk. Methods: We studied 301 patients with a first anterolateral STEMI who underwent coronary recanalization (TIMI grade 3 flow) by fibrinolysis or percutaneous coronary intervention within 6 h after symptom onset. Patients were divided into the 3 groups according to ST-segment deviation in lead aVR on admission ECG: group A, 71 patients with ST-segment elevation of ≥ 0.5 mm; group B, 131 patients without ST-segment deviation; and group C, 99 patients with ST-segment depression of ≥ 0.5 mm. Myocardial blush grade was assessed immediately after recanalization. Results: There were no differences in age, sex, coronary risk factors, time from symptom onset to admission, or multivessel disease among the 3 groups. In groups A, B, and C, the incidence of Killip class ≥ 2 was 6%, 6%, and 15% (p=0.03); the sum of ST-segment elevation in leads I, aVL, and V1– 6 was 20±11, 23±9, and 33±14 mm (p&lt;0.01); the rates of initial TIMI grade 0 or 1 flow was 56%, 70%, and 78% (p=0.01); good collateral circulation was 43%, 39%, and 22% (p=0.03); impaired myocardial reperfusion (defined as myocardial blush grade 0 or 1) was 14%, 23%, and 65% (p&lt;0.01); peak creatine kinase level was 3432±1995, 4045±2144, and 5986±2550 mU/ml (p&lt;0.01); and predischarge left ventricular ejection fraction was 56±13%, 51±11%, 44±12% (p&lt;0.01), respectively. Multivariate analysis showed that ST-segment depression in lead aVR was an independent predictor of impaired myocardial reperfusion (odds ratio 3.31, 95% CI 1.98 to 5.52, p&lt;0.001); but sum of ST-segment elevation in leads I, aVL, and V1– 6 was not. Conclusions: In patients with anterolateral STEMI, ST-segment depression in lead aVR on admission ECG is associated with less successful myocardial reperfusion and larger infarct. Assessment of ST-segment deviation in lead aVR is useful for acute risk stratification.

Catheter-Based Closure of the Patent Foramen Ovale

Case presentation: A 34-year-old woman was admitted for chest pain lasting 5 hours. She had been in excellent health except for migraine attacks with rare aura that kept her away from work about twice a month. She took no medication except for birth control pills. The ECG was unrevealing, but cardiac biomarkers were elevated. Emergency cardiac catheterization showed an occluded small left circumflex coronary artery (Figure 1) and a corresponding small akinetic area in the left ventriculogram. No attempt at coronary recanalization was made because the symptoms had abated, the injured myocardium was akinetic, and there were no collaterals. However, a catheter was introduced into the right atrium, and contrast medium injection proved the suspected patent foramen ovale (PFO; Figure 2 and Movies I and II in the online-only Data Supplement). An Amplatzer PFO occluder was implanted in <10 minutes. The patient was discharged 36 hours later after her cardiac biomarkers had normalized. Figure 1. Right anterior oblique view of the left coronary artery showing an abrupt occlusion (presumably embolic) of a small left circumflex coronary artery (arrow). Figure 2. Left, Angiographic proof of a PFO (dashed arrow) by contrast medium injection at the PFO entrance in the right atrium (RA). Right, Situation after implantation of an Amplatzer 25-mm PFO occluder (left atrium [LA] disk, 25 mm; RA disk, 18 mm). See also Movies I and II in the online-only Data Supplement. SS indicates septum secundum; SP, septum primum. Several lessons are to be gleaned from this case: (1) paradoxical embolism does not necessarily require clinically apparent deep vein thrombosis; (2) paradoxical embolism is not confined to the brain; (3) if coronary artery disease had been present, the connection to paradoxical embolism would probably have been missed; (4) attention was correctly directed primarily at the PFO with a potential to …

Clinical observation of intravenous thrombolytic therapy with urokinase in 36 cases elder patients with acute myocardial infarction

Objective To investigate elderly patients with acute myocardial infarction(AMI)after intravenous thrombolytic therapy with urokinase clinical effect.Methods From February 2006 to February 2009 in our hospital 65 patients with AMI over the age of 72 cases of old age,and randomly divided into two groups,the observation group were treated by intravenous thrombolysis with urokinase in patients with 36 cases,while the control group 36 patients given conventional treatment of oral nitrates,β-blockers,angiotensinfor-enzyme inhibitors,aspirin and heart care,symptomatic treatment.Results Coronary recanalization rate was 66.67%(24/36),4-week mortality was 5.56%(2/36),the conventional treatment group was 19.44% (7/36),two groups were statistically significant differences(P<0.05).Observer Group rate of serious arrhythmias 27.78%(10/36),the control group was 52.78%(19/36),two groups were statistically significant differences(P<0.05).Conclusion The urokinase intravenous thrombolytic therapy in elderly patients with acute myocardial infarction can improve recanalization rates,lower mortality,reduce the occurrence of heart failure and improve the prognosis of patients with improved quality of life. Key words: Urokinase; Intravenous thrombolysis; Elderly; Acute myocardial infarction

Ventricular septal defect following disobliteration of right coronary artery.

Reperfusion injury is thought to occur during coronary recanalisation but rarely produces clinically significant effects other than arrhythmia. We report an unusual case of Ventricular Septal Defect (VSD) developing after successful disobliteration of the right coronary artery. In this case clinical, electrocardiographic and biochemical evidence of myocardial injury developed 6 hours after successful percutaneous recanalization of the infarct related artery. A rapidly developing VSD soon became apparent necessitating surgical intervention to repair the defect. Unfortunately the patient died soon after surgery.

The metamorphosis of myocardial infarction following coronary recanalization

The "metamorphosis" of acute myocardial infarction (AMI) in terms of pathological features and complications in the reperfusion era is herein discussed. Typically, the AMI following coronary artery recanalization is characterized by frequent subendocardial location, since a prompt coronary lumen recanalization is able to prevent the transmural progression of myocardial necrosis from the endocardium towards the epicardium. Transmural AMI may develop when recanalization occurs late (>6 hours) or is not effective (persistent coronary occlusion). Moreover, reperfused AMI frequently appears reddish because of interstitial haemorrhage, which is thought to be caused by vascular cell damage with leakage of blood out of the injured vessels. Hemorrhage occurs always within the area of necrosis and it is significantly related to the infarct size and to the coronary occlusion time. At histology, typical features of reperfused AMI consist of contraction band necrosis and interstitial hemorrhage. Moreover, a more pronounced inflammatory cellular response is visible within the necrotic area when comparing reperfused with non-reperfused AMI. Reperfusion after prolonged coronary occlusion is also associated with secondary impairment of microcirculatory flow ("no-reflow" phenomenon), that is due to endothelial swelling, luminal obstruction and external compression but may also be aggravated by distal embolization. Finally, the reperfused AMI with its typical subendocardial, non-transmural location, is characterized by a lower incidence of expansive remodelling and related complications, in terms of cardiogenic shock, myocardial rupture, aneurysm and pseudoaneurysm formation and thromboembolism. Moreover, pericardial involvement is a rare occurrence. Unfavorable mechanical consequences of intramyocardial haemorrhage could consist in increased myocardial stiffness, propensity to wall rupture and delayed healing process. However, prospective in vivo large-scale studies in patients with reperfused AMI are needed to assess the prognostic value of hemorrhagic AMI in terms of morbidity and mortality. The knowledge and correct interpretation of these findings at post-mortem by the general and forensic pathologists is of great importance, to provide useful information to the clinicians.

Ovine Models for Chronic Heart Failure

Testing and optimizing of surgical therapies for chronic heart failure (CHF) requires large animal models. CHF has been induced in several large animal species. Sheep have modest body mass increase and demonstrate docile behavior and are therefore a preferred species in research on surgical therapies for CHF METHODS: A literature search for existing ovine CHF models was performed, using search terms "sheep" and "heart failure". Relevant secondary references were traced. Rapid ventricular pacing produces rapid-onset CHFE Its severity ranges from moderate left ventricular failure to severe biventricular failure, depending on length and frequency of pacing. Its counterpart in human CHF is tachycardia-induced HF since it is reversible upon cessation of pacing. Myocardial damage models include CHF induced by cardiototoxic drugs and ischemia. Ischemia-based models include coronary microembolization, occlusion and ischemia/reperfusion models. The microembolization model is relevant to diabetic cardiomyopathy. Coronary occlusion models exhibit variable functional impairment, some with aneurysm formation, and some with mitral valve regurgitation, depending on occlusion localization. They are relevant to CHF following non-reperfused myocardial infarction. Coronary occlusion/reperfusion models are relevant to the occurrence of human ãã despite coronary artery recanalization. Pressure overload of left and right ventricle is induced by aortic and pulmonary artery banding, respectively. Hypertrophy precedes CHF as in patients with valve stenosis and hypertension. Volume overload is induced by valve damage or shunt creation. Atrioventricular valve regurgitation is the most important clinical counterpart. Several ovine CHF models exist. Since they exhibit important cardiac pathology differences, the choice of model should be based on the specific experimental question.

Intravenous administration of adenosine triphosphate disodium during primary percutaneous coronary intervention attenuates the transient rapid improvement of myocardial wall motion, not myocardial stunning, shortly after recanalization in acute anterior myocardial infarction

Administration of adenosine attenuates myocardial stunning after reperfusion in a canine experimental ischemic model. However, it is unknown whether administration of adenosine triphosphate disodium (ATP) during reperfusion can attenuate myocardial stunning after coronary recanalization in patients with acute myocardial infarction (MI). Therefore, we sought to elucidate the effects of ATP administration on serial changes of left ventricular systolic function before and after coronary recanalization. In 27 patients with first ST-elevation acute anterior MI, in whom primary percutaneous coronary intervention (PCI) was completed within 10 h after symptom onset, ATP at a mean rate of 103 microg/kg/min (n=16) or normal saline (n=11) was intravenously administered for 1 h during reperfusion. Left ventricular regional wall motion within the initially severely ischemic region was serially analyzed using the standard wall motion score index (WMSI) by transthoracic echocardiography. Means of WMSIs were similar shortly before primary PCI in both groups (2.79 in ATP group and 2.69 in controls). They changed to 2.56 and 2.22 shortly after PCI, 2.49 and 2.39 on day 2, 2.34 and 2.30 on day 3, 2.19 and 2.25 on day 10, and 1.85 and 2.02, 6 months later, respectively. Transient improved regional wall motion within the initially severely ischemic region was observed shortly after PCI in controls (10.3% of observed segments); however, it was significantly suppressed in the ATP group (2.55%). The percent recovery of WMSI on day 10, which was defined as WMSI on day 10 normalized by improvement of WMSI for 6 months, was 63.8% in ATP group and 65.7% in controls, implying ATP administration could not reduce myocardial stunning by day 10 after primary PCI. The high-dose administration of ATP during primary PCI prevented transient improved wall motion shortly after coronary recanalization rather than preventing left ventricular stunning. These results suggest that ATP can prevent reperfusion injury during primary PCI.

Modern state of acute myocardial infarction in the interventional era: Observational case–control study—Japanese acute coronary syndrome study (JACSS)

The Japanese acute coronary syndrome study (JACSS) is a retrospective and multicenter observational study conducted in 35 medical institutions across Japan. The JACSS database included 5325 consecutive patients hospitalized at the participating institutions within 48 h after the onset of symptoms of acute myocardial infarction (AMI) between January 2001 and December 2003. The JACSS data vividly displayed the modern state of AMI in the interventional era. Percutaneous coronary intervention (PCI) including balloon angioplasty and stent implantation was performed in 80% of the patients and approximately 90% of the treated patients had successful coronary recanalization during the acute phase of MI. The results showed very low rates of all-cause mortality and cardiovascular deaths during hospitalization. Various types of novel information have been produced from JACSS data by several leading clinical researchers in Japan and this may also be helpful in making plans for a prospective study.

Electrocardiographic change after recanalization in a patient with recent extensive anterior wall myocardial infarction

In a 66-year-old male with subacute extensive anterior wall myocardial infarction, we report a change in ST vector orientation from a basal anterior to a mid anterior after coronary artery recanalization of the proximal left anterior descending coronary artery with rotational atherectomy. The ST vector shift on the frontal plane after recanalization was consistent with a change toward more distal location of the ischemia on thallium-201 single photon emission computed tomography images compared to the findings during an exercise test before intervention. These findings may be correlated with local occlusion caused by distal microvascular embolization which was not visualized on coronary angiography following recanalization.

Area at Risk and Viability after Myocardial Ischemia and Reperfusion Can Be Determined by Contrast-Enhanced Cardiac Magnetic Resonance Imaging

Background/Aims: Clinical differentiation between infarcted and viable myocardium in the ischemic area at risk is controversial. We investigated the potential of contrast-enhanced cardiac magnetic resonance imaging (ceCMRI) in determining the area at risk 24 h after ischemia. Methods: Myocardial ischemia was induced by percutaneous coronary intervention of the left anterior descending coronary artery in pigs. Coronary occlusion time was 30 min in group A, which caused little myocardial infarction and 45 min in group B, which led to irreversible damage. 24 h after reperfusion ceCMRI was performed at 2 and 15 min after administration of gadolinium-diethylenetriamine pentaacetic acid. The area at risk was determined by intravenous injection of Evans blue and myocardial viability by triphenyltetrazolium-chloride staining. Results: The signal-intense areas at 2 and 15 min after contrast administration matched the area at risk in groups A and B. Nonviable myocardium in group A was overestimated (14–15%) while good agreement was present in group B. Conclusion: The area at risk of reperfused ischemic myocardium can be determined by ceCMRI 24 h after coronary recanalization. This type of information might have relevant clinical implications in the treatment and stratification of patients with acute coronary syndrome in particular after surgical interventions.

Incidence, determinants, and prognostic value of reverse left ventricular remodelling after primary percutaneous coronary intervention: results of the Acute Myocardial Infarction Contrast Imaging (AMICI) multicenter study

AimsFew data are available on the extent and prognostic value of reverse left ventricular remodelling (r-LVR) after ST-elevation acute myocardial infarction (STEMI). We sought to evaluate incidence, major determinants, and long-term clinical significance of r-LVR in a group of STEMI patients treated with primary percutaneous coronary intervention (PPCI). In particular, the role of preserved microvascular flow within the infarct zone in inducing r-LVR has been investigated.Methods and resultsSerial echocardiograms (2DE) and myocardial contrast study were obtained within 24 h of coronary recanalization (T1) and at pre-discharge (T2) in 110 reperfused STEMI patients. Follow-up 2DE was scheduled after 6 months (T3). Two-year clinical follow-up was obtained. Reverse remodelling was defined as a reduction >10% in LV end-systolic volume (LVESV) at 6 months follow-up. r-LVR occurred in 39% of study population. At multivariable analysis, independent predictors of r-LVR were an effective microvascular reflow within the infarct zone, the in-hospital improvement of myocardial perfusion, an initial large LVESV, and a short time to reperfusion. Cox analysis identified r-LVR as the only independent predictor of 2-year event-free survival. Combined events rate was significantly higher among patients without compared to those with r-LVR (log-rank test P < 0.05).Conclusionr-LVR frequently occurs in STEMI patients treated with PPCI and it is an important predictor of favourable long-term outcome. A preserved microvascular perfusion within the infarct zone is the major determinant of r-LVR.

Pathophysiology of Ischemia-Reperfusion Injury: New Therapeutic Options for Acute Myocardial Infarction

The impact of coronary artery disease on survival and quality of life is mainly due to cardiomyocyte death. Massive cardiomyocyte death occurs during acute myocardial infarction but emergency coronary recanalization is usually not able to prevent it. Laboratory research has demonstrated that a significant part of that cell death takes place during the first few minutes of reperfusion and that treatment aimed at disrupting the mechanisms responsible can reduce the size of the infarct. Those mechanisms include Ca2+ overload, mitochondrial permeabilization and cytoskeletal and membrane fragility (induced by the activation of proteases), all of which play critical roles. Moreover, cell death can propagate to adjacent cardiomyocytes via gap junctions. In addition, other myocardial and blood cells also contribute to both immediate and delayed cardiomyocyte death during reperfusion. Most forms of treatment developed to protect against reperfusion injury are still at the experimental stage, though some have been successfully tested in patients, such as atrial natriuretic peptide, inhibition of mitochondrial permeabilization and ischemic postconditioning. The possibility that myocardial salvage can be achieved by administering adjuvant treatment during coronary recanalization presents acute myocardial infarction patients with a new therapeutic option.

The No-Reflow Phenomenon

LACK OF INTRAMYOCARDIAL REPERFUSION after successful coronary recanalization has been defined as the “no-reflow” phenomenon. The phenomenon is not uncommon (39% with myocardial contrast echocardiography [MCE] and 43% using myocardial blush grade at coronary angiography) in humans after

Abstract 2011: A Simple Nomogram to Predict the Probability of Successful Reperfusion with Pre-Hospital Thrombolysis

In ST-elevation myocardial infarction (STEMI), coronary recanalisation is a prerequisite for deriving benefit from thrombolysis, but achieving myocardial reperfusion is also key to benefit. Data regarding the impact of thrombolysis on myocardial reperfusion are scarcer than for recanalisation, especially when pre-hospital thrombolysis is considered. To develop a nomogram for predicting myocardial reperfusion after pre-hospital thrombolysis. In 2004 – 05, 800 consecutive French patients with STEMI received pre-hospital thrombolysis within 6 hours of symptom onset (median delay of 110 minutes). The assessment of myocardial reperfusion was based on the measurement of ST resolution (STR) between a first electrocardiogram (ECG), recorded before thrombolysis, and a second one in the cath laboratory. Myocardial reperfusion was assessed when STR was 70%, at least, in the single lead with the greatest baseline ST-elevation. The sample comprised 18% of women and median age was 59. The median delay between the two ECGs was 110 minutes. The proportion of patients who achieved STR was 42%. The nomogram was based on the variables that were independently associated with STR in multivariate logistic regression analysis. For instance, a non-obese smoker patient, with a non-anterior STEMI and a maximum ST-elevation of 2 mm, for whom thrombolysis is possible within 1 hour of symptom onset, together with the administration of a thienopyridine, but no IV nitrates, has a probability of 0.87 to achieve STR. If thrombolysis is delayed after one hour, without thienopyridine administration, in case of anterior STEMI, the probability declines to 0.50. The probabilities of STR for the different situations covered by the nomogram range from 0.10 to 0.87. This nomogram, developed in a “real world” setting, is designed to predict a priori the probability of myocardial reperfusion following thrombolysis, based on simple clinical and electrocardiographic data.