Classification of myocardial infarction and unstable angina: a re-assessment.

True or impending myocardial injury is being defined as an acute coronary syndrome (ACS), and includes ST-segment elevation MI, non-ST-segment elevation MI, and unstable angina. According to the revised MI definitions, patients with ischemic symptoms but with only a minor rise and fall in any biomarker are now being classified as having true myocardial injury. Against this background, this paper re-examines the position of "unstable angina" within the ACS context. It now must be acknowledged that the most recent definition of unstable angina, from 2000, which divided patients with unstable angina in those who were troponin-positive and those that remained troponin-negative, overlaps with the current MI definition. The seminal 1989 clinical definition of unstable angina thus remains the most appropriate description of that ACS entity. This "paradigm shift" has significant bearing on both the numbers of patients with non-ST-segment elevation MI, as well as on their prognosis. The same is true for patients now being diagnosed as having "unstable angina." To a large extent, future cardiovascular risk is determined by clinical parameters, and their proper assessment thus remains paramount. Elevated age, previous MI, diabetes and/or renal dysfunction and, in particular, the presence of recent onset of symptoms (Braunwald category IIIB) with concomitant ECG changes should identify those at high risk. Patients with such characteristics should benefit from thorough medical management, including extensive platelet inhibition in most and coronary revascularization in many.

Clinical classification and plaque morphology determined by optical coherence tomography in unstable angina pectoris.

Unstable angina pectoris (UAP) is categorized with the Braunwald classification. However, the association of clinical presentation and plaque structure/function has not yet been elucidated in relation to cause. We used optical coherence tomography to investigate this relation. One hundred fifteen patients with primary UAP were categorized according to the Braunwald classification. Patients with class I UAP had the highest frequency of ulcers without fibrous cap disruption (p = 0.003) and the smallest minimum lumen area (class I, median 0.70 mm(2), quartiles 1 to 3 0.42 to 1.00; class II, 1.80 mm(2), 1.50 to 2.50; class III, 2.31 mm(2), 1.21 to 3.00; p <0.001). Patients with class II UAP had the highest frequency of coronary spasm (p <0.001) and the lowest frequency of thrombi (p <0.001). Patients with class III UAP had the highest frequency of plaque ruptures (p <0.001), the thinnest fibrous cap (class I, median 140 microm, quartile 1 to 3 90 to 160; class II, 150 microm, 120 to 160; class III, 60 microm, 40 to 105; p <0.001), and the highest frequency of thin cap fibroatheromas (p <0.001) and spotty calcifications (p <0.001). In conclusion, the structures/functions of culprit lesions on optical coherence tomograms differ in the Braunwald classes of UAP. Plaque vulnerability, progressive stenosis, and vasoconstriction may be related to the cause of the distinct presentations.

[Factor analysis of traditional Chinese medicine syndromes in 815 patients with unstable angina].

OBJECTIVE: To explore the laws of traditional Chinese medicine (TCM) syndromes in unstable angina, and to establish the preliminary diagnostic criteria for TCM syndromes. METHODS: Multi-center prospective research on TCM syndromes in 815 cases of unstable angina was done with the nonlinear dimension reduction by factor analysis. RESULTS: There were five extracted factors in factor analysis: F1, F2, F3, F4 and F5. F1 was yin deficiency of heart and kidney, F2 was deficiency of both heart and spleen, F3 was intermingled phlegm and blood stasis, F4 was qi deficiency and blood stasis, and F5 was yang deficiency and coagulated cold. Qi deficiency and blood stasis (F4) syndrome accounted for the maximum proportion. The diagnostic criteria for TCM syndromes were preliminarily and respectively established. CONCLUSION: Qi deficiency and blood stasis is the key factor of pathogenesis. The factor analysis can help us classify traditional Chinese medicine syndromes and establish the preliminary diagnostic criteria.

Positive predictive value of ICD-9 codes 410 and 411 in the identification of cases of acute coronary syndromes in the Saskatchewan Hospital automated database.

BACKGROUND: Case definitions are essential to epidemiological research. OBJECTIVES: To evaluate ICD-9 codes 410 and 411 to identify cases of acute coronary syndromes (ACS), and the clinical information availability in the administrative and hospital discharge records of Saskatchewan, Canada. METHODS: In the context of a safety cohort study, we identified hospitalisations with primary discharge codes 410 (2260) and 411 (799). We selected all records with code 411, and a random sample (200) with code 410. Based on information obtained by trained abstractors from hospital records, events were classified by two cardiologists as definite or possible according to adapted AHA/ESC criteria. The validity of 410 and 411 codes was assessed by calculating the positive predictive value (PPV). Completeness of the recorded information on risk factors and use of aspirin was explored. RESULTS: The PPVs of the codes 410 and 411 for ACS were 0.96 (95%CI: 0. 92-0.98) and 0.86 (95%CI: 0.83-0.88), respectively. The PPV of 410 for acute myocardial infarction (AMI) was 0.95 (95%CI: 0.91-0.98). The PPV of 411 was 0.73 (95%CI: 0.70-0.77) for primary unstable angina (UA) and 0.09 (95%CI: 0.07-0.11) for AMI. Hospital charts review revealed key information for clinical variables, smoking, obesity and use of aspirin at admission. CONCLUSIONS: ICD-9 410 code has high PPV for AMI cases, likewise 411 for UA cases. Case validation remains important in epidemiological studies with administrative health databases. Given the pathophysiology of ACS, both AMI and UA might be used as study end points. In addition to code 410, we recommend the use of 411 plus validation.

[Clinical morphology of acute coronary syndrome].

The paper describes acute coronary syndrome and gives its definition, classification and current possibilities of its clinical and morphological diagnosis. Emphasis is laid on the troponine test and clinicoinstrumental imaging of coronary arterial obstruction and myocardial ischemia. Data on the morphological criteria for vulnerable atherosclerotic plaque, different stages of ischemia and early myocardial necrosis are presented. Recommendations on establishing the postmortem diagnosis of acute coronary syndrome are given.

Angiographic extent of coronary artery stenosis in patients with high and intermediate likelihood of unstable angina according to likelihood classification of American Heart Association.

OBJECTIVE: In accordance with the AHA/ACC clinical practice guideline, the likelihood of acute ischemia caused by coronary artery disease (CAD) is to be determined as high, intermediate, or low for all patients presenting with chest discomfort. This study was conducted to estimate extent of significant CAD in patients with high and intermediate likelihood of unstable angina (UA) according to "AHA likelihood classification". METHODS: Overall, 133 consecutive patients presented with symptoms or signs suggestive of UA, which was classified as of high or intermediate likelihood in Emergency Department (ED), and undergoing coronary angiography (CAG) within one week were enrolled into the study. The characteristics of the patients in either subgroup were compared in terms of the findings of the CAG. RESULTS: In patients with high likelihood of UA (n=89), CAG revealed that 62 had significant CAD, 7-moderate CAD, 20-mild CAD or normal coronary angiogram. In patients with intermediate likelihood of UA (n=19), CAG revealed that 2 patients had significant CAD, and 17-mild CAD or normal coronary angiogram. The rate of significant CAD was significantly higher in patients with high likelihood (p<0.001, LR 23.97, 95% CI 4.21-90.43). The sensitivity and specificity of having at least one of high likelihood features for detecting significant CAD were found to be 96.8% and 38.6% respectively. CONCLUSION: We suggest that the likelihood classification is useful for the triage of the UA patients in the ED. When supported with further studies, utilization of this classification will yield a high diagnostic accuracy in predicting or ruling out severe CAD in patients presenting with chest pain.

[Cluster analysis on TCM syndromes in 319 coronary artery disease patients for establishment of syndrome diagnostic figure].

OBJECTIVE: To explore the diagnostic figures for TCM syndrome typing in coronary heart disease (CHD) patients. METHODS: A retrospective investigation was carried out in 319 CHD patients hospitalized from Jan. 2004 to Dec. 2004 in authors' hospital. Through cluster analysis, descriptive statistics and frequency normalization in combination of clinical observation, the diagnostic figures of TCM syndromes were obtained. RESULTS: The figures for qi deficiency syndrome were: primary symptoms: chest pain and stuffiness, secondary symptoms: tiredness, short breath, poor appetite, light colored tongue, deep and thready pulse; for qi deficiency with phlegm and blood stasis syndrome: primary symptoms: chest stuffiness and pain, secondary symptoms: tiredness, insomnia, palpitation, obesity, dark red tongue, string and slippery pulse; for turbid-phlegm blocking collateral syndrome: primary symptoms: chest stuffiness, secondary symptoms: cough, expectoration with much white sputum, tiredness, short breath and poor appetite, light colored tongue with white greasy coating, slippery pulse. CONCLUSION: Research on diagnostic criteria for TCM syndrome typing could be established upon clinical epidemiologic survey and statistic analysis in combining with specialists' suggestions to primarily set the referrence figures.

Unstable angina patients treated with percutaneous coronary intervention in the new millennium: what characterizes them?

OBJECTIVE: To identify clinical and angiographic profiles of patients with unstable angina seen at a tertiary hospital and treated with percutaneous coronary intervention (PCI). METHODS: Study of a consecutive series of 1413 patients, selected from a computerized database, who underwent percutaneous revascularization in the three-year period of 2002-2004. There were no inclusion/exclusion criteria. RESULTS: Systemic arterial hypertension (74%) and hypercholesterolemia (65%) were the classical risk factors for coronary disease most frequently observed. Coronary artery bypass grafting and history of myocardial infarction were found in 24% and 28% of the cases, respectively. The subgroups most commonly treated were the IIB (48%) and IIIB (28%). Clopidogrel was prescribed for 51% of the patients and glycoprotein IIb/IIIa inhibitors, for 7%. Multivessel disease evidenced by coronary angiography was detected in 42% of the cases. Type B2 or C lesions were treated in 64%, 94% of which in native vessels. Restenotic lesions were dilated in 5% of the patients. All interventions were performed using coronary stents, the majority of which (67%) were standard bare-metal stents. CONCLUSIONS: 1) Subgroups IIB and IIIB were the most frequently treated (76%); 2) Clopidogrel was the most prescribed antithrombotic agent (51%); 3) Multivessel coronary artery disease was found in 42% of the cases, most of which were complex target lesions located in native vessels; 4) Coronary stent implantation was the chief dilation technique used.

Pacientes com angina instável tratados por meio de intervenções coronarianas percutâneas no novo milênio: o que os caracteriza? / Unstable angina patients treated with percutaneous coronary intervention in the new millennium: what characterizes them?

OBJETIVO: Identificar os perfis clínico/angiográfico e relacionados ao procedimento de pacientes com angina instável atendidos em um hospital terciário e tratados por meio de intervenções coronarianas percutâneas. MÉTODOS: Estudo de uma casuística consecutiva de 1.413 pacientes, selecionados a partir de um banco de dados informatizado e revascularizados percutaneamente no triênio 2002-2004. Não houve critérios de inclusão/exclusão. RESULTADOS: Hipertensão arterial sistêmica (74 por cento) e hipercolesterolemia (65 por cento) foram os fatores de risco clássicos para doença coronariana mais observados. Antecedentes de infarto do miocárdio e cirurgia de revascularização miocárdica foram respectivamente observados em 28 por cento e 24 por cento dos casos. Os subgrupos mais comumente tratados foram o IIB (48 por cento) e IIIB (28 por cento). O clopidogrel foi prescrito a 51 por cento dos pacientes, enquanto os inibidores IIb IIIa foram utilizados em 7 por cento. Doença coronariana multiarterial na cinecoronariografia diagnóstica ocorreu em 42 por cento dos casos. Lesões-alvo tipo B2 ou C foram tratadas em 64 por cento, das quais 94 por cento situavam-se em vasos naturais. Lesões reestenóticas foram dilatadas em 5 por cento dos pacientes. Todas as intervenções foram realizadas utilizando os stents coronarianos, a maioria dos quais (67 por cento) do tipo convencional. CONCLUSÕES: 1) os subgrupos IIB e IIIB foram os mais comumente tratados (76 por cento); 2) o clopidogrel foi o antitrombótico mais prescrito (51 por cento); 3) a coronariopatia multiarterial foi observada em 42 por cento dos casos, com predomínio de lesões-alvo complexas e situadas em vasos naturais; 4) a técnica de dilatação predominante foi o implante dos stents coronarianos.

OBJECTIVE: To identify clinical and angiographic profiles of patients with unstable angina seen at a tertiary hospital and treated with percutaneous coronary intervention (PCI). METHODS: Study of a consecutive series of 1413 patients, selected from a computerized database, who underwent percutaneous revascularization in the three-year period of 2002-2004. There were no inclusion/exclusion criteria. RESULTS: Systemic arterial hypertension (74 percent) and hypercholesterolemia (65 percent) were the classical risk factors for coronary disease most frequently observed. Coronary artery bypass grafting and history of myocardial infarction were found in 24 percent and 28 percent of the cases, respectively. The subgroups most commonly treated were the IIB (48 percent) and IIIB (28 percent). Clopidogrel was prescribed for 51 percent of the patients and glycoprotein IIb/IIIa inhibitors, for 7 percent. Multivessel disease evidenced by coronary angiography was detected in 42 percent of the cases. Type B2 or C lesions were treated in 64 percent, 94 percent of which in native vessels. Restenotic lesions were dilated in 5 percent of the patients. All interventions were performed using coronary stents, the majority of which (67 percent) were standard bare-metal stents. CONCLUSIONS: 1) Subgroups IIB and IIIB were the most frequently treated (76 percent); 2) Clopidogrel was the most prescribed antithrombotic agent (51 percent); 3) Multivessel coronary artery disease was found in 42 percent of the cases, most of which were complex target lesions located in native vessels; 4) Coronary stent implantation was the chief dilation technique used.

[Prognostic stratification in non-ST-elevation acute coronary syndromes: how and why]. / Sindromi coronariche acute: identificare l'alto rischio attraverso una corretta stratificazione prognostica. Perché e come.

Prognostic stratification is essential for the correct management of acute coronary syndromes (ACS). Across the whole spectrum of ACS, prognosis is strongly differentiated and also easy to establish. Shock identifies a small subgroup of patients including more than 50% of total mortality of acute ST-elevation myocardial infarction (STEMI). In non-ST-elevation (NSTE) ACS and in STEMI, heart failure represents a clinical variable with a strong prognostic value: in the GRACE registry only 15% of patients had heart failure with a mortality of 12.4 vs 1.1% in the other patients without heart failure; this important difference was interestingly evident in non-STEMI as well as in STEMI. Age is another pivotal risk indicator like heart rate and systolic blood pressure. It is noteworthy that the prognostic benefit deriving from resource utilization increases in ACS with the level of personal risk. This is true for the use of primary angioplasty in national registries of STEMI as well as for the early invasive strategy in NSTE-ACS in several trials; conversely, the use of aggressive strategies in low-risk ACS populations is often lacking of relevant results on hard endpoints. In our healthcare system with limited resources and with an inhomogeneous structure across the country, regionalization of care is the most efficient choice. Scientific Italian Societies redefined risk criteria for ACS in order to ensure priority to complex care for high-risk subgroups.

Are we appropriately triaging patients with unstable angina?

BACKGROUND: It is uncertain how aggressively patients should be monitored and admitted to the hospital for chest pain syndromes and if the monitoring itself affects patient care, process, or outcomes. We assessed the appropriateness of care based on retrospective analysis of admission bed assignment (nonmonitored vs monitored) and Thrombolysis in Myocardial Infarction (TIMI) risk score in patients from the Global Unstable Angina Registry and Treatment Evaluation (GUARANTEE) Registry. METHODS: Baseline characteristics, process of care, and outcomes were compared among 2939 patients admitted to 1 of 35 hospitals in the United States. Patients were stratified into low (0-2), intermediate (3 or 4), and high (5-7) risk based on TIMI risk score. RESULTS: Among the patients, 92 (3%) were admitted to the cardiac care unit (CCU), 1602 (56%) were admitted to the telemetry unit, and 1163 (41%) were admitted to an unmonitored bed. Paradoxically, high-risk patients comprised only 1% of those in the CCU, 5% of those in telemetry, and 10% of those in nonmonitored units. Conversely, low-risk patients were 64% of those in the CCU, 53% of those in telemetry, and 42% of those in unmonitored beds. Procedures were done more often on patients admitted to nonmonitored units than those on telemetry or in the CCU irrespective of TIMI risk score. CONCLUSIONS: This registry suggests that triage of patients does not routinely follow the risk-based approach suggested in the American College of Cardiology and American Heart Association guidelines and could therefore potentially lead to inefficiencies in care. Better implementation of risk stratification for acute coronary syndrome evaluation and management is necessary.