Cardiovascular Outcomes of Sitagliptin in Type 2 Diabetic Patients with Acute Myocardial Infarction, a Population-Based Cohort Study in Taiwan

Background

The cardiovascular safety and efficacy of sitagliptin, a dipeptidyl peptidase 4 (DPP-4) inhibitor, in type 2 diabetic patients after acute myocardial infarction (AMI) has so far remained uncertain.

Methods

We analyzed data from the National Health Insurance Research Database (NHIRD), a government-operated, population-based database, from March 1st, 2009 to December 31st, 2011. Type 2 diabetic patients hospitalized for AMI were included in our study. We compared subjects using sitagliptin with comparison group to evaluate its cardiovascular safety and efficacy. The primary endpoint was a composite of cardiovascular death, myocardial infarction, and ischemic stroke.

Results

We identified a total of 3,282 type 2 diabetic patients hospitalized for AMI (mean follow-up 1.15 years). Of these patients, 547 (16.7%) who were exposed to sitagliptin were defined as the sitagliptin group and 2,735 (83.3 %) who did not use sitagliptin were the comparison group. The incidence of primary composite cardiovascular outcomes was 9.50 per 100 person-years in the sitagliptin group and was 9.70 per 100 person-years in the comparison group (hazard ratio (HR), 0.97; 95% CI, 0.73–1.29, P=0.849). Compared to the non-sitagliptin group, the sitagliptin group had similar risks of all-cause mortality, hospitalization for heart failure (HF) or percutaneous coronary intervention (PCI) with a HR of 0.82 (95% CI, 0.61–1.11, P=0.195), 0.93 (95% CI, 0.67–1.29, P=0.660), and 0.93 (95% CI, 0.75–1.14, P=0.473), respectively.

Conclusion

The use of sitagliptin in type 2 diabetic patients with recent AMI was not associated with increased risk of adverse cardiovascular events.

Detection of indoxyl sulfate levels in dogs and cats suffering from naturally occurring kidney diseases

Indoxyl sulfate (IS), a protein-bound uraemic toxin, has been found to accumulate in the serum of people with renal diseases and is associated with free radical induction, nephrotoxicity cardiovascular toxicity, and osteoblast cytotoxicity. Although IS has been studied in humans and in experimental models, the role of IS in dogs and cats with kidney disease has not been investigated. A high performance liquid chromatography system was applied to detect plasma IS concentrations in non-azotaemic animals (63 dogs, 16 cats) and in animals with renal azotaemia (66 dogs, 69 cats). The IS levels of azotaemic animals were significantly higher (P <0.01) than those of non-azotaemic animals (median [IQR] 20.4 (9.5) mg/L vs. 7.2 (8.8) mg/L for dogs; median [IQR] 21 (18.9) mg/L vs. 14.8 (12.3) mg/L for cats). The IS level was significantly correlated with blood urea nitrogen, serum creatinine and phosphate concentrations. Dogs with acute kidney injury had significantly higher IS levels (P <0.01) than those with chronic kidney diseases (CKD) (median [IQR] 57.7 (40.8) mg/L vs. 17.7 (25.1) mg/L). When CKD was graded using the International Renal Interest Society (IRIS) staging system, IS levels were correlated with CKD severity in both dogs and cats. The IS concentration is directly related to loss of renal function. Further studies are necessary to determine whether measurement of IS provides any additional diagnostic or prognostic information in dogs and cats with kidney disease.

Clinical and angiographic outcomes after intracoronary bare-metal stenting

Background

Data from a large patient population regarding very long-term outcomes after BMS implantation are inadequate. This study aimed to evaluate the very long-term (8–17 years) clinical and long-term (3–5 years) angiographic outcomes after intracoronary bare-metal stenting (BMS).

Methods and Results

From the Cardiovascular Atherosclerosis and Percutaneous TrAnsluminal INterventions (CAPTAIN) registry, a total of 2391 patients with 2966 lesions treated with 3190 BMSs between November 1995 and May 2004 were evaluated. In total, 1898 patients with 2364 lesions, and 699 patients with 861 lesions underwent 6-month and 3- to 5- year angiographic follow-up, respectively. During a mean follow-up period of 149±51 months, 18.6% of the patients died (including 10.8% due to cardiac death), 6.1% developed reinfarction, 16.2% had target lesion revascularization (including 81% of the patients within the first year), 14.5% underwent new lesion stenting (including 72% of the patients after 3 years), 2.4% underwent coronary bypass surgery, and 1.6% had definite stent thrombosis. The overall cardiovascular event-free survival rate was 58.5%. The 6-month angiographic study indicated a 20% restenosis rate. The minimal luminal diameter increased from 0.65±0.44 mm to 3.02±0.46 mm immediately after stenting, decreased to 2.06±0.77 mm at the 6-month follow-up, and increased to 2.27±0.68 mm at the 3- to 5-year follow-up.

Conclusions

This study provides clinical and angiographic results from a large population of patients who underwent BMS implantations after a long-term follow-up period (149±51 months). The progression of coronary atherosclerosis developed over time, and presented with new lesion required stent implantation. The follow-up angiographic findings reconfirmed the late and sustained improvement in luminal diameter between 6 months and 3–5 years.

Enhancement of diabetic wound repair using biodegradable nanofibrous metformin-eluting membranes: in vitro and in vivo

This work developed biodegradable nanofibrous drug-eluting membranes that provided sustained release of metformin for repairing wounds associated with diabetes. To prepare the biodegradable membranes, poly-d-l-lactide-glycolide (PLGA) and metformin were first dissolved in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) and were spun into nanofibrous membranes by electrospinning. An elution method and an HPLC assay were utilized to characterize the in vivo and in vitro release rates of the pharmaceuticals from the membranes. The biodegradable nanofibrous membranes released high concentrations of metformin for more than three weeks. Moreover, nanofibrous metformin-eluting PLGA membranes were more hydrophilic and had a greater water-containing capacity than virgin PLGA fibers. The membranes also improved wound healing and re-epithelialization in diabetic rats relative to the control. The experimental results in this work suggest that nanofibrous metformin-eluting membranes were functionally active in the treatment of diabetic wounds and very effective as accelerators in the early stage of healing of such wounds.

Dual protection therapy with staged coronary artery bypass surgery and stenting in patients with left main coronary artery stenosis: long-term results from a single center

OBJECTIVE

We evaluated the efficacy and safety of dual protection therapy with staged coronary artery bypass grafting (CABG) and bare-metal stenting (BMS) in patients with left main coronary artery (LMCA) disease.

BACKGROUND

CABG is currently the preferred therapy for complex LMCA disease; however, the long-term patency rates of these grafts are unsatisfactory, and stenting alone for LMCA may be associated with the potentially fatal consequences of stent thrombosis or restenosis.

METHODS

Between January 1997 and October 2005, 42 patients underwent staged bypass surgery and BMS, with the latter procedure performed 2 weeks after the initial CABG. Of these patients, 40 received left internal mammary artery (LIMA) grafts, 34 saphenous vein grafts, 6 radial artery grafts, and 3 right IMA (RIMA) grafts. Minimally invasive bypass surgery was performed in 10 patients.

RESULTS

There were no operative complications. Forty-two stents were implanted in 42 lesions without complications. During the follow-up period of 135 ± 55 months, 1 patient died of cancer, 2 of cardiac causes, and 5 patients (12%) experienced target lesion revascularization. The target vessel failure rate was 24%. Forty patients (95%) underwent a 6-month angiographic follow-up. Restenosis was noted in 7 patients (18%). Reocclusion was also noted in 5 LIMA grafts, 5 saphenous vein grafts, 1 radial artery graft, and 1 RIMA graft. Only 1 patient experienced both restenosis of LM stenting and total occlusion of the 2 bypass grafts.

CONCLUSIONS

Dual protection therapy with staged CABG and stenting is not an appropriate therapeutic strategy because of unacceptable graft patency rate. A higher occlusive rate of the bypass grafts may result from decreased blood flow because of competing blood flow between the bypass graft and the native coronary vessel.

Local sustained delivery of acetylsalicylic acid via hybrid stent with biodegradable nanofibers reduces adhesion of blood cells and promotes reendothelialization of the denuded artery

Incomplete endothelialization, blood cell adhesion to vascular stents, and inflammation of arteries can result in acute stent thromboses. The systemic administration of acetylsalicylic acid decreases endothelial dysfunction, potentially reducing thrombus, enhancing vasodilatation, and inhibiting the progression of atherosclerosis; but, this is weakened by upper gastrointestinal bleeding. This study proposes a hybrid stent with biodegradable nanofibers, for the local, sustained delivery of acetylsalicylic acid to injured artery walls. Biodegradable nanofibers are prepared by first dissolving poly(D,L)-lactide-co-glycolide and acetylsalicylic acid in 1,1,1,3,3,3-hexafluoro-2-propanol. The solution is then electrospun into nanofibrous tubes, which are then mounted onto commercially available bare-metal stents. In vitro release rates of pharmaceuticals from nanofibers are characterized using an elution method, and a highperformance liquid chromatography assay. The experimental results suggest that biodegradable nanofibers release high concentrations of acetylsalicylic acid for three weeks. The in vivo efficacy of local delivery of acetylsalicylic acid in reducing platelet and monocyte adhesion, and the minimum tissue inflammatory reaction caused by the hybrid stents in treating denuded rabbit arteries, are documented. The proposed hybrid stent, with biodegradable acetylsalicylic acid-loaded nanofibers, substantially contributed to local, sustained delivery of drugs to promote re-endothelialization and reduce thrombogenicity in the injured artery. The stents may have potential applications in the local delivery of cardiovascular drugs. Furthermore, the use of hybrid stents with acetylsalicylic acid-loaded nanofibers that have high drug loadings may provide insight into the treatment of patients with high risk of acute stent thromboses.

The prognostic significance of SYNTAX score after early percutaneous transluminal coronary angioplasty for acute ST elevation myocardial infarction

INTRODUCTION

SYNergy between percutaneous coronary intervention (PCI) with TAXUS and Cardiac Surgery (SYNTAX) score, which is based on the characteristics of atherosclerotic lesions and the complexity of coronary artery anatomy, is useful for choosing an intervention strategy, but its prognostic significance for acute ST elevation of myocardial infarction (STEMI) remains unknown. This study aimed to redress this issue.

METHODS

Our observational study included 151 consecutive patients admitted for acute STEMI who underwent primary PCI between January 1, 2008 and December 31, 2009. The primary endpoint for analysis was 30-day cardiac death.

RESULTS

Among the 151 patients, cardiac death occurred in 10 (7%) within 30 days. After the first month, five patients died of non-cardiac causes, but no cardiac death occurred. Multivariate analysis showed that SYNTAX score (odds ratio [OR], 13.79, 95% confidence interval [CI], 1.24-153.38; p=0.033) and a symptom onset-to-therapy time interval >4 h (OR, 11.13; 95% CI, 1.08-114.42; p=0.043) were independent risk factors for 30-day mortality. The SYNTAX score cut-off for discriminating low and high risk was 22.

CONCLUSIONS

SYNTAX score is an independent predictor of short-term cardiac mortality in patients with acute STEMI.

Lesion length impacts long term outcomes of drug-eluting stents and bare metal stents differently

BACKGROUND

Long lesions have been associated with adverse outcomes in percutaneous coronary interventions with bare metal stents (BMS). However, the exact impact of lesion length on the short- and long-term outcomes of drug-eluting stent (DES) implantations is not as clear.

METHODS AND RESULTS

This study compared the impact of lesion length on angiographic and clinical outcomes of BMS and DES in a single-center prospective registry. Lesion length was divided into tertiles. The primary endpoints were angiographically defined binary in-stent restenosis (ISR) rate and major adverse cardiac event (MACE). Of the 4,312 de novo lesions in 3,447 consecutive patients in the CAPTAIN registry, 2,791 lesions (of 2,246 patients) received BMS, and the remaining 1,521 lesions (of 1,201 patients) received DES. The mean follow-up duration was 4.5 years. The longer the lesion, the higher the ISR rate (14%, 18%, and 29%, p<0.001) and the lower the MACE-free survivals (p = 0.007) in the BMS group. However, lesion length showed no such correlation with ISR rates (4.7%, 3.3%, and 7.8%, p = 0.67) or MACE-free survivals (p = 0.19) in the DES group.

CONCLUSIONS

In our single-center prospective registry, lesion length defined in tertiles has no impact on the short-term (ISR) or long-term (MACE) outcomes of patients implanted with DES. In contrast, longer lesion correlates with higher ISR and MACE rates in BMS group.

Renal dysfunction on admission, worsening renal function, and severity of acute kidney injury predict 2-year mortality in patients with acute myocardial infarction

BACKGROUND

Recent studies have proven that initial renal dysfunction and worsening renal function during hospitalization can predict the clinical outcome of patients with acute myocardial infarction (AMI). There is limited study regarding acute kidney injury (AKI) by the RIFLE classification (Risk of renal failure, Injury to the kidney, Failure of kidney function, Loss of kidney function, and End-stage renal failure) to assess the outcome of AMI survivors.

METHODS AND RESULTS

During a mean follow-up period of 635.3 ± 204.9 days, the 2-year mortality rate was 10.6% in 613 AMI patients who survived to discharge. Adjusted Cox regression analysis revealed that left ventricular dysfunction (<40%) [hazard ratio (HR), 2.83; 95% confidence interval (CI), 1.11-7.20; P=0.029], estimated glomerular filtration rate <60 ml min(-1) x 1.73 m(-2) on admission (HR, 4.01; 95% CI, 1.51-10.62; P=0.005), and AKI severity by RIFLE classification during first week after hospitalization (Injury: HR, 8.11; 95% CI, 2.53-26.05; P=0.001; Failure: HR, 19.28; 95% CI, 2.24-166.26; P=0.007) were independent predictors of 2-year mortality.

CONCLUSIONS

Independent of initial renal dysfunction on admission, the AKI severity by RIFLE classification may be useful in establishing the hospital discharge risk score for predicting long-term mortality in AMI patients who survive to discharge.

Paraoxonase-1 is not a major determinant of stent thrombosis in a Taiwanese population

Background

Clopidogrel is a prodrug that undergoes in vivo bioactivation to show its antiplatelet effects. Recent studies have shown that cytochrome P450 (CYP), ATP-binding cassette transporters (ABCB1), and paraoxonase-1 (PON1) play crucial roles in clopidogrel bioactivation. Here, we aim to determine the effects of genetic polymorphisms of CYP (CYP 2C19*2, CYP 2C19*3, and CYP 2C19*17), ABCB1 (ABCB1 3435C>T, ABCB1 129T>C, and ABCB1 2677G>T/A), and PON1 (PON1 Q192R, PON1 L55M, and PON1 108C>T) on the development of stent thrombosis (ST) in patients receiving clopidogrel after percutaneous coronary intervention (PCI).

Methods and Results

We evaluated the incidence of ST (0.64%) in 4964 patients who were recruited in the CAPTAIN registry (Cardiovascular Atherosclerosis and Percutaneous TrAnsluminal INterventions). The presence of genetic polymorphisms was assessed in 20 subjects who developed ST after aspirin and clopidogrel therapy and in 40 age- and sex-matched control subjects who did not develop ST, which was documented after 9 months of angiographic follow-up. ST was acute in 5 subjects, subacute in 7, late in 7, and very late in 1. The presence of CYP 2C19*2 allele was significantly associated with ST (adjusted odds ratio [ORadj]: 4.20, 95% confidence interval [CI], 1.263–9.544; P = 0.031). However, genetic variations in PON1 and ABCB1 showed no significant association with ST.

Conclusion

We conclude that in a Taiwanese population, PON1 Q192R genotype is not associated with ST development after PCI. However, the presence of CYP 2C19*2 allele is a risk factor for ST development after PCI.

Reversible left ventricular diastolic dysfunction on Doppler tissue imaging predicts a more favorable prognosis in chronic heart failure

BACKGROUND

Early (e')/late (a') diastolic mitral annular velocity ratio is a powerful independent predictor of poor prognosis in patients with left ventricular (LV) dysfunction. Doppler tissue imaging, however, may change over time according to intervention and medical treatment. The aim of the present study was to prospectively evaluate whether, in clinically stable patients with chronic heart failure (CHF), the decrease of an initially high e'/a' ratio on long-term therapy predicts a more favorable outcome.

METHODS AND RESULTS

One hundred and eighty-one adult patients with CHF and high e'/a' ratio (≥ 0.74) underwent repeat echocardiography 6 months after the initial examination, and were then followed up for a mean period of 20 months. After 6 months, e'/a' ratio did not change in 95 patients, whereas it was significantly decreased (<0.74) in the remaining 86 patients. During follow-up, 55 participants (30%) had cardiac events. According to multivariate Cox regression analysis, decrease in e'/a' ratio, initial New York Heart Association class III or IV, and change in LV mass index as well as in systolic mitral annular velocities emerged as independent predictors of survival.

CONCLUSIONS

The decrease of an initially high e'/a' ratio on long-term therapy predicts a more favorable outcome in clinically stable patients with CHF.

Dynamic aortic pouch: a rare etiology of aortic regurgitation

The causes of aortic regurgitation (AR) include rheumatic heart disease, infective endocarditis, and various congenital and degenerative defects. We report an unusual case of AR in a 72-year-old man due to an aortic root pouch. The diagnosis AR was made by cardiac echocardiography, and the cause was revealed by cardiac catheterization and 64-slice cardiac computed tomography. During aortic valve replacement, a saccular pouch between the noncoronary cusp and the right coronary cusp of the aortic valve was noted.

Salvage surgery after failed chemoradiotherapy in squamous cell carcinoma of the esophagus

AIMS

To investigate the survival benefit and preoperative risk factors for hospital mortality of salvage surgery in esophageal cancer patients who had locoregional residual/recurrent tumor after definitive chemoradiotherapy.

METHODS

We retrospectively reviewed the esophageal cancer patients who presented at our hospital from 1997 to 2004. Forty-seven patients who had squamous cell cancer and developed locoregional recurrent/persistent disease after primary definitive chemoradiotherapy were elected. Twenty-seven of them received salvage esophagectomy (group 1) and the other 20 underwent non-operative treatment only (group 2). In order to assess the surgery-related mobility and mortality in group 1, 191 patients who received neoadjuvant chemoradiotherapy followed by operation during the same time period were also enrolled (group 3).

RESULTS

The 5-year overall survival of group 1 patients was 25.4%. In contrast, all of the patients in the group 2 died within 16.7 months. The difference was statistically significant (p=0.0029). In comparison with group 3, group 1 patients had significantly more surgery-related complications and hospital mortality. In univariate analysis for preoperative risk factors, a low albumin or hemoglobulin level was associated with high hospital mortality in group 1 (p=0.004 and 0.003, respectively). After multivariate analysis, only the low albumin level remained borderline significance. As for disease specific survival after salvage surgery, R0 resection was the only independent prognosticator (p=0.049).

CONCLUSION

Salvage surgery provides survival benefit in esophageal cancer patients with locoregional persistent or recurrent disease after primary definitive chemoradiotherapy. Preoperative albumin and hemoglobulin levels are associated with hospital mortality and may aid in selecting suitable patient for salvage surgery.

Permanent pacing using a coronary sinus lead in a patient with univentricular physiology: an extended application of biventricular pacing technology

In the past, patients requiring permanent pacing with difficult right ventricular (RV) access were usually subjected to epicardial pacing by a surgical approach. This report describes a young patient with univentricular physiology following repeated palliative surgery for complex congenital heart disease. The patient had symptomatic complete heart block and a dual chamber pacemaker with transvenous atrial and ventricular leads was implanted successfully. The ventricle was paced through the posterolateral cardiac vein with a lead specially designed for cardiac resynchronization therapy. This case illustrates an extended application of the recently developed coronary sinus lead in selected patients, when conventional RV endocardial pacing is impossible.

Levels of interferon-gamma and interleukin-2 receptor-alpha for bronchoalveolar lavage fluid and serum were correlated with clinical grade and treatment of pulmonary tuberculosis

OBJECTIVE

We investigated possible correlations for interferon-gamma (IFN-gamma) and soluble interleukin-2 receptor-alpha (sIL-2R-alpha) levels in bronchoalveolar lavage fluid (BALF), and clinical grade of pulmonary tuberculosis (TB), which is determined by factors such as extent of pulmonary involvement, fever and loss of body weight.

DESIGN

In order to explore these correlations and address associated questions, BALF was collected from 45 patients presenting with active pulmonary TB and 14 healthy controls. Repetitive BALF was collected in 17 patients after 3 months of anti-tuberculosis chemotherapy. The epithelial lining fluid (ELF) levels for IFN-gamma and sIL-2R-alpha were measured using enzyme-linked immunosorbent assay (ELISA) after standardization with urea.

RESULTS

Patients with higher-grade pulmonary TB (i.e., with more advanced pulmonary involvement, fever or body weight loss), revealed significantly higher ELF levels for IFN-gamma and sIL-2R-alpha compared to those with lower grade pulmonary TB. Similar results were also determined for sIL-2R-alpha serum levels, but not for IFN-gamma serum levels. After anti-tuberculosis chemotherapy the elevated cytokine levels for ELF and serum significantly decreased in accordance with radiographic improvement.

CONCLUSIONS

ELF levels of IFN-gamma and sIL-2R-alpha were correlated with disease grading of pulmonary TB and decreased after anti-tuberculosis chemotherapy.

Combined bronchoalveolar lavage and polymerase chain reaction in the diagnosis of pulmonary tuberculosis in smear-negative patients

SETTING

The polymerase chain reaction (PCR) may be sensitive and specific for the diagnosis of tuberculosis, but most reports are of studies conducted in well-controlled laboratories. A study to evaluate the clinical value of bronchoalveolar lavage (BAL) combined with PCR was necessary.

OBJECTIVE

One hundred and thirty one patients were recruited into the study from March 1994 to February 1997.

DESIGN

Patients with a positive acid-fast stain on sputum smear were recruited into group A as positive controls, patients with lung cancer and a negative acid-fast stain on sputum smear were put into group B as negative controls, and patients who had clinical symptoms of pulmonary TB without sputum or with negative smear results were the investigating group. PCR was performed on the sputum samples from group A and B patients and on the BAL fluid from those in group C.

RESULTS

The sensitivity of PCR was 96% in group A, and the specificity was 100% in group B. The sensitivity of PCR in the BAL fluid from the group C patients was 36% and the specificity was 96%; the positive predictive value was 94% and the negative predictive value was 45%.

CONCLUSION

BAL plus PCR is useful in the rapid diagnosis of pulmonary TB in non-productive or smear-negative patients.

Minimal access thoracic surgery for esophageal hemangioma

Esophageal hemangioma is a rare tumor. This report describes the case of a 69-year-old woman with an esophageal tumor at the middle portion of the esophagus. The patient was successfully treated with minimal access thoracic surgery, and at the 6 month follow-up, the patient was free of any symptoms or recurrence.

Paradoxical cerebral air embolism after removal of a central venous catheter: case report

Paradoxical cerebral air embolization through a residual tract after the removal of a central venous catheter is a serious complication of central venous cannulation. Air embolisms resulting from residual catheter tracts in general patients and in single lung transplant patients have been reported. The generally accepted mechanism of this complication is failure of a spontaneous collapse or thrombotic obliteration of a well-formed catheter tract. It may be related to the duration of catheter insertion, the patient's nutritional status, the diameter of the indwelling catheter, the upright position of the patient, deep inspiration or coughing, and improper wound dressing and catheter removal. Cardiovascular collapse, pulmonary or neurologic sequelae, and even death, are commonly noted in patients with air embolism. In this article, we report on cerebral air embolization as a complication with the removal with a central venous catheter in a patient with bullous emphysema. A high degree of suspicion and a prompt diagnosis are required for successful application of established therapy. Simple prophylactic procedures and constant awareness of the unusual mechanism of air embolism remain the best treatment.

Anomalous systemic arterialization to normal basal segments of the left lower lobe: helical CT and CTA findings

PURPOSE

The purpose of this work was to evaluate the helical CT and CT angiography (CTA) findings of anomalous systemic artery (ASA) to the basal segments of the left lower lobe (LLL).

METHOD

Three patients (two had hemoptysis, one was asymptomatic) with blotchy nodular density in the LLL revealed on chest radiographs underwent helical CT and CTA. Bronchoscopy was performed in two of these patients. Angiography and surgery were performed in one patient.

RESULTS

All three patients demonstrated characteristic helical CT and CTA findings including 1) a sigmoid-shaped ASA originating from the lower descending thoracic aorta, with a distal bulbous configuration and four arterial branches supplying the basal segments of the LLL; 2) absence of an interlobar pulmonary artery or presence of a small artery lateral to the truncus basalis; 3) engorged vascular markings in the basal segments of the LLL; and 4) normal tracheobronchial tree and lung parenchyma.

CONCLUSION

The findings in the present three cases suggest that the use of invasive studies such as angiography or bronchoscopy may be obviated in the diagnosis of ASA to the LLL because diagnosis can be provided through a clear set of criteria on helical CT and CTA.