Scholarly article on topic 'Clinical profile and outcomes of primary percutaneous coronary intervention in young patients'

Clinical profile and outcomes of primary percutaneous coronary intervention in young patients Academic research paper on "Health sciences"

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{"Myocardial infarction" / "Percutaneous coronary intervention" / "Coronary artery disease" / "Infarto do miocárdio" / "Intervenção coronária percutânea" / "Doença da artéria coronariana"}

Abstract of research paper on Health sciences, author of scientific article — Ivan Petry Feijó, Márcia Moura Schmidt, Renato Budzyn David, João Maximiliano Pedron Martins, Karine Elisa Schmidt, et al.

Abstract Background The epidemiology of acute myocardial infarction with ST-segment elevation (STEMI) has been modified in recent years, focusing on young people. Our goal was compare the clinical profile, laboratory, angiographic, and 30-day clinical outcomes of patients ≤ 40 years with those > 40 years undergoing primary percutaneous coronary intervention (pPCI). Methods Prospective cohort study of consecutive patients undergoing pPCI between 2009 and 2011. Results A total of 1,055 patients were included, 3.3% of them ≤ 40 years. Young patients were more often black, smokers and with a family history of coronary artery disease, and less often hypertensive and dyslipidemic. In patients ≤ 40 years, leukocyte count and ultrasensitive troponin levels at admission were higher, and high density lipoprotein-cholesterol, lower. The left anterior descending artery as a culprit vessel and left ventricular ejection fraction did not differ between groups. Although the TIMI 3 flow pre-intervention was similar, young people showed higher prevalence of myocardial blush 3 pre-procedure. The door-to-balloon time was lower in younger patients (1.0 hour [0.8-1.4 hour] vs. 1.3 hour [0.9-1.7 hour]; p = 0.03). At 30 days, patients ≤ 40 years had a mortality of 0% vs. 8.8% for patients > 40 years (p = 0.07). Conclusions Patients ≤ 40 years with STEMI and undergoing pPCI show differences in clinical, angiographic and procedural characteristics compared to those > 40 years. In this analysis, representative of the current medical practice, the 30-day mortality of these patients was very low.

Academic research paper on topic "Clinical profile and outcomes of primary percutaneous coronary intervention in young patients"

Rev Bras Cardiol Invasiva. 2015;23(1):48-51

Original

Clinical profile and outcomes of primary percutaneous coronary intervention in young patients

Ivan Petry Feijó, Márcia Moura Schmidt, Renato Budzyn David, Joäo Maximiliano Pedron Martins, Karine Elisa Schmidt, Carlos Antonio Mascia Gottschall, Alexandre Schaan de Quadros*

Instituto de Cardiología do Rio Grande do Sul, Fundafäo Universitaria de Cardiologia, Porto Alegre, RS, Brazil

ARTICLE INFO ABSTRACT

Background: The epidemiology of acute myocardial infarction with ST-segment elevation (STEMI) has been modified in recent years, focusing on young people. Our goal was compare the clinical profile, laboratory, angiographic, and 30-day clinical outcomes of patients < 40 years with those > 40 years undergoing primary percutaneous coronary intervention (pPCI).

Methods: Prospective cohort study of consecutive patients undergoing pPCI between 2009 and 2011. Results: A total of 1,055 patients were included, 3.3% of them < 40 years. Young patients were more often black, smokers and with a family history of coronary artery disease, and less often hypertensive and dyslipidemic. In patients < 40 years, leukocyte count and ultrasensitive troponin levels at admission were higher, and high density lipoprotein-cholesterol, lower. The left anterior descending artery as a culprit vessel and left ventricular ejection fraction did not differ between groups. Although the TIMI 3 flow pre-intervention was similar, young people showed higher prevalence of myocardial blush 3 pre-procedure. The door-to-balloon time was lower in younger patients (1.0 hour [0.8-1.4 hour] vs. 1.3 hour [0.9-1.7 hour]; p = 0.03). At 30 days, patients < 40 years had a mortality of 0% vs. 8.8% for patients > 40 years (p = 0.07). Conclusions: Patients < 40 years with STEMI and undergoing pPCI show differences in clinical, angiographic and procedural characteristics compared to those > 40 years. In this analysis, representative of the current medical practice, the 30-day mortality of these patients was very low.

© 2015 Sociedade Brasileira de Hemodinamica e Cardiología Intervencionista. Published by Elsevier Editora Ltda.

This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/Iicenses/by-nc-nd/4.0/).

Perfil clínico e resultados da intervençâo coronária percutânea primária em pacientes jovens

RESUMO

Introdujo: A epidemiología do infarto agudo do miocárdio com supradesnivelamento do segmento ST (IAMCST) tem se modificado nos últimos anos, com incidencia maior em jovens. Nosso objetivo foi comparar o perfil clínico, laboratorial e angiográfico, e os desfechos clínicos em 30 dias de pacientes < 40 anos aqueles > 40 anos submetidos a intervengo coronária percutanea primária (ICPp). Métodos: Estudo de coorte prospectivo com pacientes consecutivos submetidos a ICPp entre 2009 e 2011. Resultados: No período, 1.055 pacientes foram incluidos, sendo identificados 3,3% com < 40 anos. Pacientes jovens eram mais frequentemente negros, tabagistas e com historia familiar de doenga coronária, e menos frequentemente hipertensos e dislipidemicos. Nos pacientes < 40 anos, a dosagem de leucocitos e da troponina ultrassensível na admissao foi maior, e a lipoproteína de alta densidade-colesterol, menor. A artéria descendente anterior como vaso culpado e a fragao de ejegao do ventrículo esquerdo nao foram diferentes entre os grupos. Apesar de o fluxo TIMI 3 pré ser similar, os jovens mostraram maior prevalencia de blush miocárdico 3 pré-procedimento. O tempo porta-balao foi menor nos pacientes mais jovens (1,0 hora [0,8-1,4 hora] vs. 1,3 hora [0,9-1,7 hora]; p = 0,03). Em 30 dias, os pacientes < 40 anos apresentaram mortalidade de 0% vs. 8,8% nos pacientes > 40 anos (p = 0,07).

DOI of original article: http://dx.doi.org/10.1016/j.rbci.2015.01.006

* Corresponding author: Avenida Princesa Isabel, 370, Santana, CEP: 90620-000, Porto Alegre, RS, Brazil. E-mail: alesq@terra.com.br (A.S. de Quadros).

Peer Review under the responsability of Sociedade Brasileira de Hemodinamica e Cardiologia Intervencionista.

2214-1235/© 2015 Sociedade Brasileira de Hemodinamica e Cardiologia Intervencionista. Published by Elsevier Editora Ltda. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/Iicenses/by-nc-nd/4.0/).

Article history:

Received 11 November 2014

Accepted 17 January 2015

Keywords:

Myocardial infarction Percutaneous coronary intervention Coronary artery disease

Palavras-chave: Infarto do miocárdio Intervençâo coronária percutânea Doença da artéria coronariana

Conclusoes: Pacientes < 40 anos com IAMCST e submetidos a ICPp apresentam diferengas nos perfis clínico, angiográfico e do procedimento quando comparados aqueles > 40 anos. Nesta análise, representativa da prática médica atual, a mortalidade em 30 dias desses pacientes foi muito baixa.

© 2015 Sociedade Brasileira de Hemodinamica e Cardiología Intervencionista. Publicado por Elsevier Editora Ltda. Este é um artigo Open Access sob a licenca de CC BY-NC-ND (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Introduction

Cardiovascular diseases are the leading cause of mortality in Brazil and worldwide. Acute myocardial infarction (AMI) is the cardiovascular disease with greatest mortality, and its incidence in young patients has increased over the years.1-3 Currently, the incidence in patients under 40 years is around 4%-10%.4-7

In several studies, it was observed that myocardial infarction in young patients is most often associated with smoking, family history of coronary artery disease, and dyslipidemia.4578 However, there are few Brazilian studies evaluating this question.

The objective of this study was to evaluate the clinical and angio-graphic characteristics as well as the clinical outcome for young patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCl) in contemporary clinical practice.

Methods

Patients

All patients diagnosed with AMI admitted to this institution from December 1st, 2009 to December 31st, 2011 were prospectively evaluated. Inclusion criteria were clinical and electrocardiographic diagnosis of myocardial infarction, and indication for pPCl by the attending physician. Exclusion criteria were At > 12 hours, age < 18 years, and refusal to sign the informed consent.

STEMI was defined as the presence of a typical pain at rest associated to ST-segment elevation in two contiguous leads of at least 1 mm in the frontal plane or 2 mm in the horizontal plane, or the presence of a typical chest pain at rest in patients with a new left bundle branch block.

Patients were categorized into two groups: patients aged < 40 years and controls (> 40 years). The clinical characteristics and outcomes were compared. The study was approved by the Ethics Committee of this institution.

Percutaneous procedure

The Hemodynamics Service of this institution operates fulltime, 24 hours a day, 7 days a week. Approximately 500 pPCl procedures are performed annually. The institutional routine is an acetylsalicylic acid loading dose of 300 mg and clopidogrel 300600 mg at admission to emergency department and heparin 60100 U/kg. pPCl procedures are performed as described in the literature.9 Specific technical aspects, such as access route, drug administration, type of stent, and thromboaspiration, are at operators' discretion.

Clinical, laboratory, and angiographic evaluation

The clinical interview was conducted by trained researchers. Demographics, risk factors for ischemic heart disease, medical history, and clinical presentation of the event data were collected. Laboratory tests were conducted according to the institutional criteria and included, among others, serum glucose concentration, renal function, and inflammation and myocardial necrosis markers.

Angiographic evaluations were performed by a digital electronic system AXIOM Artis (Siemens, Munich, Germany). Target vessel reference diameter was defined as the average of proximal and distal diameters from the lesion, and stenosis severity was evaluated in two orthogonal projections; the most severe was considered, both before and after stent implantation. The lesion length was measured shoulder-to-shoulder and lesions with a normal arterial segment < 10 mm between them were considered as a single lesion. The coronary flow before and after the procedure was evaluated and described according to Thrombolysis In Myocardial Infarction (TIMl) criteria. Myocardial perfusion was assessed by myocardial blush, as previously described.10

30-day clinical outcomes

The 30-day follow-up was conducted by phone, and occurrences of death, stroke, reinfarction, need for a new percutaneous or surgical revascularization, and/or stent thrombosis were registered.

Statistical analysis

SPSS version 17.0 for Windows was used for statistical analysis. Continuous variables were presented as mean and standard deviation, and compared using Student's t-test. Continuous variables with non-normal distribution were described as median and interquartile range and compared using the Mann-Whitney test. Categorical variables were described as absolute number and percentage and compared by the Chi-squared test or Fisher's exact test, as appropriate. Statistical significance was defined by a two-tailed p-value < 0.05.

Results

During the study period, 1,055 patients were included, of whom 35 (3.3%) were aged < 40 years. The mean age of young patients was 34.1 ± 4.5 years and 61.3 ± 11.1 years for those aged > 40 years. Table 1 shows the clinical characteristics of both groups. African descent, smoking, and family history of premature coronary artery disease were more frequent among patients < 40 years. On the contrary, younger patients were less frequently affected by hypertension or dyslipidemia, and this group had lower rates of previous percutaneous revascularization. The prevalence of diabetes mellitus was similar. The door-to-balloon time was lower in patients aged < 40 years (1.0 h [0.8-1.4 h] vs. 1.3 h [0.9-1.7 h]; p = 0.03).

Table 2 describes laboratory characteristics of each group. In patients aged < 40 years, the leukocyte count and ultrasensitive troponin level at admission were higher, and the high-density lipoprotein cholesterol (HDL-C) level was lower. There was no significant difference in other markers of myocardial necrosis or inflammation between groups.

Table 3 shows angiographic and procedural characteristics; note that three-vessel involvement, left anterior descending artery as the culprit vessel, and left ventricular ejection fraction did not differ between groups. Although there was equivalence of pre-procedural TlMl-3 flows, the younger group had a higher prevalence of grade 3 myocardial blush before the procedure. The reference diameter was similar, but younger patients showed shorter lesions.

Table 1

Clinical characteristics.

< 40 years > 40 years

Characteristics (n = 35) (n = 1,020) p-value

Female, n (%) 12 (34.3) 330 (32.4) 0.57

African descent, n (%) 7 (20.0) 87 (8.5) 0.02

Hypertension, n (%) 9 (25.7) 700 (68.6) < 0.01

Dyslipidemia, n (%) 6 (17.1) 369 (36.2) 0.04

Currently smoking, n (%) 24 (68.6) 447 (43.8) < 0.01

Diabetes mellitus, n (%) 7 (20.0) 235 (23.0) 0.90

Family history of CAD, n (%) 18 (51.4) 336 (32.9) < 0.01

Prior angina, n (%) 8 (22.9) 422 (41.4) 0.07

Previous myocardial infarction, n (%) 3 (8.6) 219 (21.5) 0.18

Previous stroke, n (%) 0 (0) 68 (6.7) 0.13

Prior PCl, n (%) 1 (2.9) 165 (16.2) 0.05

Prior CABG, n (%) 0 (0) 45 (4.4) 0.23

Chronic renal failure, n (%) 0 (0) 31 (3.0) 0.32

Anterior myocardial infarction, n (%) 17 (48.6) 460 (45.1) 0.40

Chronic use of ASA, n (%) 2 (5.7) 299 (29.3) < 0.01

Creatinine clearance, mL/min 125.4 ± 40.4 81.5 ± 33.2 < 0.01

BMl, kg/m2 27.8 ± 4.8 26.9 ± 4.25 0.31

Waist circumference, cm 94.3 ± 12.9 94.7 ± 14.3 0.86

Systolic blood pressure, mmHg 131.0 ± 27.8 134.8 ± 30.4 0.46

Diastolic blood pressure, mmHg 78.8 ± 14.0 81.9 ± 18.5 0.33

Heart rate, beats/minute 81.4 ± 16.1 78.9 ± 20.0 0.48

Delta t, h 4.0 (2.5-6.4) 3.5 (1.6-6) 0.27

Door-to-balloon time, h 1.0 (0.8-1.4) 1.3 (0.9- 1.7) 0.03

CAD: coronary artery disease; PCI: percutaneous coronary intervention; CABG: coronary artery bypass graft; ASA: acetylsalicylic acid.

Table 2

Laboratory characteristics.

HDL-C: high-density lipoprotein cholesterol; CRP: C-reactive protein; CK: creatine Phosphokinase; CK-MB: creatine kinase-MB isoenzyme; US: ultrasensitive.

Table 3

Angiographic and procedural characteristics.

The use of glycoprotein Ilb/llla inhibitors was higher among young patients.

During hospitalization, there were no differences between groups as to the need for mechanical ventilation (8.6% vs. 9.3%; p = 0.98), acute renal failure (5.7% vs. 4.1%, p = 0.54), or sepsis (2.9% vs. 3.6%, p = 0.88). In patients aged < 40 years, no clinical events, except for reinfarction (2.9% vs. 5.1%, p = 0.61), occurred in the first 30 days (Table 4).

Discussion

This study analyzed the clinical and angiographic profiles and clinical outcomes of patients < 40 years of age who had STEMI in a tertiary cardiology center. Among younger patients, African descent, smoking, and family history of ischemic heart disease were more frequent, but no difference for diabetes mellitus frequency was noted. Younger patients had other comorbidities and multivessel disease less often and there was a trend for a better clinical outcome after 30 days in this group. In Brazil, contemporary studies analyzing the clinical characteristics of young patients with AMI are few,1211 and it is believed that the data presented here can contribute to the development of public health policies and prevention campaigns.

This study showed high prevalence of smoking in younger patients with AMI (around 70%), which is consistent with reports from other studies that included patients with the same age group. This association has been identified in most published studies, with a prevalence of 65% to 95%.512-18 Smoking plays an important role in the genesis, progression and destabilization of atherosclerotic plaques, and its specific association with younger patients is important and deserves further evaluation.

A significantly higher frequency of a positive family history of ischemic heart disease in young patients analyzed in this study represents another important aspect. Family history is also a classic risk factor for ischemic heart disease, and the data presented in this study are also consistent with other reports in the literature.19-21 The influence of a genetic factor and its greater association in this age group are other important aspects, considering the pathophysiology and possible predisposing factors for AMI in patients < 40 years of age.

Among younger patients, African descent was more frequent vs. patients over 40 years. This finding has not been described in previous studies evaluating patients with STEMI in this age group. The influence of genetic traits or associations among socioeconomic and cultural factors, the adherence to medications, and lifestyle could explain these findings, and deserve to be better evaluated in Brazilian populations.

The diagnosis of dyslipidemia was less common in younger patients, but they had lower HDL-C levels vs. older patients. Kaukola et al.22 also showed similar values for total cholesterol in younger patients and in those over 40 years, but with HDL values slightly lower in younger patients, with a slightly higher triglyceride level in this group. A low level of HDL has been associated with acute myocardial infarction in young patients.23 Some studies indicated only high cholesterol level as a risk factor,5172425 but the establishment of an association with other laboratory findings is essential, in order to prevent

Table 4

Clinical outcomes in 30 days.

Characteristic < 40 years (n = 35) > 40 years (n = 1,020) p-value

Death, n (%) 0 (0) 95 (9.3) 0.07

Stroke, n (%) 0 (0) 9 (0.8) 0.59

Reinfarction, n (%) 1 (2.9) 52 (5.1) 0.61

Urgent CABG, n (%) 0 (0) 6 (0.6) 0.66

Stent thrombosis, n (%) 0 (0) 28 (2.7) 0.34

CABG: coronary artery bypass graft.

< 40 years > 40 years

Characteristic (n = 35) (n = 1,020) p-value

LAD lesion, n (%) 16 (45.7) 444 (43.5) 0.26

Three-vessel lesion, n (%) 4 (11.4) 193 (18.9) 0.40

Ejection fraction, % 59.6 ± 9.3 55.8 ± 11.6 0.48

TIMI 3 flow, n (%)

Pre-procedural 8 (22.9) 226 (22.2) 0.52

Post-procedural 27 (77.1) 903 (88.5) 0.07

Blush grade 3, n (%)

Pre-procedural 8 (22.9) 142 (13.9) 0.04

Post-procedural 18 (51.4) 682 (66.9) 0.91

Reference diameter, mm 3.2 ± 0.6 3.1 ± 0.4 0.61

Pre-procedural diameter stenosis, % 92.5 ± 20.2 97.3 ± 7.4 0.21

Lesion length, mm 14.8 ± 3.8 17.8 ± 8.6 < 0.01

Thromboaspiration, n (%) 13 (37.1) 369 (36.2) 0.31

Glycoprotein IIb/IIIa, n (%) 13 (37.1) 285 (27.9) 0.03

Stent diameter, mm 3.2 ± 0.5 3.1 ± 0.4 0.49

Stent length, mm 18.2 ± 4.7 19.8 ± 6.5 0.12

Deployment pressure, atm 13.8 ± 2.3 14.2 ± 2.5 0.46

Post-procedural diameter stenosis, % 0.0 ± 0.0 4.5 ± 18.3 < 0.01

LAD: left anterior descendent coronary.

<40 year > 40 year

Characteristics (n = 35) (n = 1,020) p-value

Total cholesterol, mg/dL 204.5 ± 60.8 202.1 ± 49.1 0.80

HDL-C, mg/dL 35.6 ± 14.3 40.7 ± 11.6 0.03

Triglycerides, mg/dL 120.0 (91.0- 259.5) 114.0 (75.0-177.0) 0.16

Creatinine, mg/dL 0.85 (0.7-1.1) 0.95 (0.8-1.1) 0.06

Blood glucose, mg/dL 124.5 (111.5-177.5) 143.0 (119.0-184.0) 0.11

Hematocrit, % 41.0 ± 4.3 40.6 ± 4.8 0.64

Hemoglobin, g/dL 13.9 ± 1.4 13.6 ± 1.7 0.35

Platelets, mm3 290,840.0 ± 127,872.2 250,909 ± 75,569.3 0.13

Leukocytes, mm3 16.018.1± 6.493.0 12,708.2 ± 4,355.4 < 0.01

Potassium, mEq/L 4.6 ± 0.9 4.3 ± 0.6 0.08

CRP, mg/dL 0.7 (0.26- 1.09) 0.45 (0.21-1.0) 0.20

Fibrinogen, mg/dL 239.2 ± 71.4 243.7 ± 83.9 0.81

CK, U/L 258 (79-550) 130 (57-408) 0.06

CK-MB ng/dL 18 (5-45) 11 (6- 30) 0.58

Troponin, ng/mL 0.30 (0.5-2.4) 0.40 (0.4-2.0) 0.93

US troponin, ng/dL 1,424 (109-8,480) 215 (46-1,103) 0.02

diseases in this age group. An association between dyslipidemia and AMI at an early age has been documented in other studies.12

In the present study, the early clinical outcome of younger patients was better vs. patients over 40 years, although without statistical significance. These findings are also consistent with most studies, which pointed to a lower incidence of adverse outcomes in young patients, and this could be due to a better capacity for regeneration and of response to injury and to a lower association with comorbidities.458

Conclusions

The frequency of acute myocardial infarction with ST-segment elevation in patients < 40 years of age is small, but these patients have different clinical and laboratory characteristics and early clinical outcomes vs. older patients. Population studies, with larger numbers of patients in Brazil, are important for a better understanding of this problem, as well as to guide prevention and public health campaigns.

Funding sources

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), through a scientific initiation grant for the author Karine Elisa Schmidt.

Conflicts of interest

The authors declare no conflicts of interest.

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