594498 research-article2015
ACC0010.1177/2048872615594498European Heart Journal: Acute Cardiovascular CareYamada et al.
EUROPEAN SOCIETY OF CARDIOLOGY ®
Original scientific paper
Clinical implications of pleural effusion in patients with acute type B aortic dissection
European Heart Journal: Acute Cardiovascular Care 1–10 © The European Society of Cardiology 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/2048872615594498 acc.sagepub.com
Yoshihiro Yamada1, Jun Tanno1, Shintaro Nakano1, Takatoshi Kasai2, Takaaki Senbonmatsu1 and Shigeyuki Nishimura1
Abstract Background: Pleural effusion may complicate acute Stanford type B aortic dissection (ABAD). Aims: To identify the relationships between the quantity and side of the pleural effusion, biomarkers and outcomes in patients with ABAD. Methods: We undertook a retrospective review of 105 patients with ABAD. Their demographics, the data on admission and during hospital stay, the volume of pleural effusion calculated from the area on computed tomography images and clinical outcomes were analysed. Results: The median estimated peak volume (median 6.7 days after onset) was 129 ml (63–192, range 26–514 ml) on the left and 11 ml (6–43, range 2–300 ml) on the right. On univariate analysis, the volume of bilateral effusions was associated with anaemia, hypoalbuminaemia and inflammatory markers, whereas the volume of left-sided effusions was associated with older age, low diastolic blood pressure and maximum aortic diameter. Multivariate analysis revealed that hypoalbuminaemia was independently associated with bilateral effusion volume (P24 hours after symptom onset or who did not undergo initial CT within 24 hours of onset were excluded, as CT findings at baseline were needed to determine that the development of pleural effusion was directly attributable to ABAD, and thus to exclude
patients with pre-existing effusions. Patients without serial CT examinations were also excluded, including two patients who sustained pre-hospital aortic rupture and cardiopulmonary arrest. In total, 105 patients were included in the analysis (Figure 1).
Data collected at baseline Baseline patient demographic characteristics including age, sex and body mass index were recorded. Aetiology and history were recorded, including Marfan’s syndrome, treated and untreated hypertension, dyslipidaemia, diabetes mellitus, chronic kidney disease, cancer, autoimmune disease, current smoking, history of cardiovascular disease (for example aortic aneurysm, aortic dissection, peripheral artery disease) and prior cardiovascular intervention (for example aortic surgery/endovascular intervention, valvular surgery, coronary bypass surgery, percutaneous coronary intervention). Treated hypertension was defined as treatment with an antihypertensive drug, while untreated hypertension was defined as being previously diagnosed with hypertension but without ongoing medical treatment. Diabetes mellitus was defined as treatment with antidiabetic medication (insulin or oral hypoglycaemic drugs) or a glycated haemoglobin level ⩾6.5% (National Glycohaemoglobin Standardization Program).9 Drug history before admission was reviewed. Vital signs (systolic and diastolic blood pressure, heart rate, respiratory rate and peripheral oxygen saturation) obtained in the emergency department were also recorded. We also collected echocardiographic variables obtained on admission, including left ventricular ejection fraction assessed using Teichholz’s method and the presence of severe valvular disease. Laboratory findings at admission included white blood cell count, platelet count and the concentrations of haemoglobin, D-dimers, serum creatinine, CRP and albumin.
CT examination Non-electrocardiography (ECG)-gated CT images were acquired with a LightSpeed VCT 64 (GE Healthcare, Little Chalfont, UK) generating axial images with contiguous 5 mm
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Yamada et al.
Figure 2. Aortic diameters at different levels and their associations with peak pleural effusion volumes. The aortic diameter was measured at three levels: (a) the aortic arch, (b) the proximal descending thoracic aorta (TA) and (c) the distal descending TA. In the descending TA, the maximum diameter in each segment was recorded. The boundary between the proximal and distal segments of the descending TA was the midpoint between the origin of the left subclavian artery and the diaphragm.
sections from the top of the neck vessels to the femoral artery. Enhanced CT was performed with a bolus injection of 100 ml of ionic or non-ionic contrast medium for patients weighing >50 kg, and 2 ml/kg for patients weighing 5 days).
Management, complications and endpoints Following cardiovascular rehabilitation, patients were discharged from hospital and subsequently followed up at our centre for at least one year; however, the care of those that resided far from our institution was transferred to a more convenient local hospital earlier if their recovery was uneventful (median follow-up period 36 days, range 9–2127 days). The clinical endpoints were all-cause mortality, cardiovascular mortality and requirement for emergent (inhospital) or elective surgery or endovascular treatment during the follow-up period. The length of hospital stay, ICU stay and requirement for supplementary oxygen were recorded. Inhospital complications related to ABAD were recorded such as hypotension requiring inotropic support, respiratory failure requiring unplanned endotracheal intubation, stroke, visceral ischaemia, limb ischaemia, paralysis and renal failure requiring haemodialysis.
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Yamada et al.
Statistical analysis Continuous data are reported as the mean ± standard deviation (SD) or the median (first–third quartile) and categorical data as the number (proportion). Associations between continuous variables were evaluated using Spearman’s test and the strength of correlation was expressed using the correlation coefficient (r). Univariate comparisons between the groups were performed using Wilcoxon’s rank sum test for unpaired values or Wilcoxon’s signed-rank test for paired values. Multivariate analysis to identify the independent variables associated with peak pleural effusion volume was performed using stepwise multiple linear regression analysis with forward and backward selection methods (P0.20 for exclusion). The independent variables significantly associated with peak left or right-sided effusion volume in the univariate analysis were included in the multivariate models. A generalised linear regression model with Poisson distribution was used to evaluate the impact of pleural effusion on the length of ICU and hospital stay, and oxygen use, because these are typically discrete variables with skewed distributions.14 A P value
ACC0010.1177/2048872615594498European Heart Journal: Acute Cardiovascular CareYamada et al.
EUROPEAN SOCIETY OF CARDIOLOGY ®
Original scientific paper
Clinical implications of pleural effusion in patients with acute type B aortic dissection
European Heart Journal: Acute Cardiovascular Care 1–10 © The European Society of Cardiology 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/2048872615594498 acc.sagepub.com
Yoshihiro Yamada1, Jun Tanno1, Shintaro Nakano1, Takatoshi Kasai2, Takaaki Senbonmatsu1 and Shigeyuki Nishimura1
Abstract Background: Pleural effusion may complicate acute Stanford type B aortic dissection (ABAD). Aims: To identify the relationships between the quantity and side of the pleural effusion, biomarkers and outcomes in patients with ABAD. Methods: We undertook a retrospective review of 105 patients with ABAD. Their demographics, the data on admission and during hospital stay, the volume of pleural effusion calculated from the area on computed tomography images and clinical outcomes were analysed. Results: The median estimated peak volume (median 6.7 days after onset) was 129 ml (63–192, range 26–514 ml) on the left and 11 ml (6–43, range 2–300 ml) on the right. On univariate analysis, the volume of bilateral effusions was associated with anaemia, hypoalbuminaemia and inflammatory markers, whereas the volume of left-sided effusions was associated with older age, low diastolic blood pressure and maximum aortic diameter. Multivariate analysis revealed that hypoalbuminaemia was independently associated with bilateral effusion volume (P24 hours after symptom onset or who did not undergo initial CT within 24 hours of onset were excluded, as CT findings at baseline were needed to determine that the development of pleural effusion was directly attributable to ABAD, and thus to exclude
patients with pre-existing effusions. Patients without serial CT examinations were also excluded, including two patients who sustained pre-hospital aortic rupture and cardiopulmonary arrest. In total, 105 patients were included in the analysis (Figure 1).
Data collected at baseline Baseline patient demographic characteristics including age, sex and body mass index were recorded. Aetiology and history were recorded, including Marfan’s syndrome, treated and untreated hypertension, dyslipidaemia, diabetes mellitus, chronic kidney disease, cancer, autoimmune disease, current smoking, history of cardiovascular disease (for example aortic aneurysm, aortic dissection, peripheral artery disease) and prior cardiovascular intervention (for example aortic surgery/endovascular intervention, valvular surgery, coronary bypass surgery, percutaneous coronary intervention). Treated hypertension was defined as treatment with an antihypertensive drug, while untreated hypertension was defined as being previously diagnosed with hypertension but without ongoing medical treatment. Diabetes mellitus was defined as treatment with antidiabetic medication (insulin or oral hypoglycaemic drugs) or a glycated haemoglobin level ⩾6.5% (National Glycohaemoglobin Standardization Program).9 Drug history before admission was reviewed. Vital signs (systolic and diastolic blood pressure, heart rate, respiratory rate and peripheral oxygen saturation) obtained in the emergency department were also recorded. We also collected echocardiographic variables obtained on admission, including left ventricular ejection fraction assessed using Teichholz’s method and the presence of severe valvular disease. Laboratory findings at admission included white blood cell count, platelet count and the concentrations of haemoglobin, D-dimers, serum creatinine, CRP and albumin.
CT examination Non-electrocardiography (ECG)-gated CT images were acquired with a LightSpeed VCT 64 (GE Healthcare, Little Chalfont, UK) generating axial images with contiguous 5 mm
Downloaded from acc.sagepub.com at CMU Libraries - library.cmich.edu on November 9, 2015
3
Yamada et al.
Figure 2. Aortic diameters at different levels and their associations with peak pleural effusion volumes. The aortic diameter was measured at three levels: (a) the aortic arch, (b) the proximal descending thoracic aorta (TA) and (c) the distal descending TA. In the descending TA, the maximum diameter in each segment was recorded. The boundary between the proximal and distal segments of the descending TA was the midpoint between the origin of the left subclavian artery and the diaphragm.
sections from the top of the neck vessels to the femoral artery. Enhanced CT was performed with a bolus injection of 100 ml of ionic or non-ionic contrast medium for patients weighing >50 kg, and 2 ml/kg for patients weighing 5 days).
Management, complications and endpoints Following cardiovascular rehabilitation, patients were discharged from hospital and subsequently followed up at our centre for at least one year; however, the care of those that resided far from our institution was transferred to a more convenient local hospital earlier if their recovery was uneventful (median follow-up period 36 days, range 9–2127 days). The clinical endpoints were all-cause mortality, cardiovascular mortality and requirement for emergent (inhospital) or elective surgery or endovascular treatment during the follow-up period. The length of hospital stay, ICU stay and requirement for supplementary oxygen were recorded. Inhospital complications related to ABAD were recorded such as hypotension requiring inotropic support, respiratory failure requiring unplanned endotracheal intubation, stroke, visceral ischaemia, limb ischaemia, paralysis and renal failure requiring haemodialysis.
Downloaded from acc.sagepub.com at CMU Libraries - library.cmich.edu on November 9, 2015
5
Yamada et al.
Statistical analysis Continuous data are reported as the mean ± standard deviation (SD) or the median (first–third quartile) and categorical data as the number (proportion). Associations between continuous variables were evaluated using Spearman’s test and the strength of correlation was expressed using the correlation coefficient (r). Univariate comparisons between the groups were performed using Wilcoxon’s rank sum test for unpaired values or Wilcoxon’s signed-rank test for paired values. Multivariate analysis to identify the independent variables associated with peak pleural effusion volume was performed using stepwise multiple linear regression analysis with forward and backward selection methods (P0.20 for exclusion). The independent variables significantly associated with peak left or right-sided effusion volume in the univariate analysis were included in the multivariate models. A generalised linear regression model with Poisson distribution was used to evaluate the impact of pleural effusion on the length of ICU and hospital stay, and oxygen use, because these are typically discrete variables with skewed distributions.14 A P value
