A case of aortic dissection with transient ST-segment elevation due to functional left main coronary artery obstruction

Clinical Predictors for Delayed or Inappropriate Initial Diagnosis of Type A Acute Aortic Dissection in the Emergency Room

BACKGROUND

Initial diagnosis of acute aortic dissection (AAD) in the emergency room (ER) is sometimes difficult or delayed. The aim of this study is to define clinical predictors related to inappropriate or delayed diagnosis of Stanford type A AAD.

METHODS

We conducted a retrospective analysis of 127 consecutive patients with type A AAD who presented to the ER within 12 h of symptom onset (age: 69.0 ± 15.4 years, male/female = 49/78). An inappropriate initial diagnosis (IID) was considered if AAD was not included in the differential diagnosis or if chest computed tomography or echocardiography was not performed as initial imaging tests. Clinical variables were compared between IID and appropriate diagnosis group. The time to final diagnosis (TFD) was also evaluated. Delayed diagnosis (DD) was defined as TFD > third quartile. Clinical factors predicting DD were evaluated in comparison with early diagnosis (defined as TFD within the third quartile). In addition, TFD was compared with respect to each clinical variable using a rank sum test.

RESULTS

An IID was determined for 37% of patients. Walk-in (WI) visit to the ER [odds ratio (OR) 2.6, 95% confidence interval (CI) = 1.01-6.72, P = 0.048] and coronary malperfusion (CM, OR = 6.48, 95% CI = 1.14-36.82, P = 0.035) were predictors for IID. Overall, the median TFD was 1.5 h (first/third quartiles = 0.5/4.0 h). DD (>4.5 h) was observed in 27 cases (21.3%). TFD was significantly longer in WI patients (median and first/third quartiles = 1.0 and 0.5/2.85 h for the ambulance group vs. 3.0 and 1.0/8.0 h for the WI group, respectively; P = 0.003). Multivariate analysis revealed that WI visit was the only predictor for DD (OR = 3.72, 95% CI = 1.39-9.9, P = 0.009). TFD was significantly shorter for appropriate diagnoses than for IIDs (1.0 vs. 6.0 h, respectively; P < 0.0001).

CONCLUSIONS

WI visit to the ER and CM were predictors for IID, and WI was the only predictor for DD in acute type A AAD in the community hospital.

Electrocardiographic changes in patients with type A acute aortic dissection. Incidence, patterns and underlying mechanisms in 159 cases

BACKGROUND

Not only symptoms but electrocardiographic (ECG) changes mimicking acute coronary syndrome as well have been known to develop in acute aortic dissection (AAD). However, detailed information is lacking.

OBJECTIVE

We sought to evaluate incidence, patterns, and underlying mechanisms for acute ECG changes in type A AAD.

METHODS

Retrospective study in a single tertiary care hospital. A total of 159 cases (mean age 65.1±14.8 years, male/female=67/92) that presented within 12 h from the onset were included. Shift of the ST segment ≥0.1 mV or changes of the T wave were considered acute ECG changes.

RESULTS

Acute and chronic ECG changes were observed in 49.7% and 36.5% cases, respectively. ECG was normal only in 27.0% cases. ST elevation was observed in 8.2% cases and was closely related to direct coronary involvement. ST depression and T wave changes were observed in 34.0% and 21.4% cases, respectively. Cases with ST depression or T wave changes had higher incidence of shock (65.2% vs. 28.8%, p<0.001) and cardiac tamponade (51.2% vs. 15.0%, p<0.001) compared with those without changes.

CONCLUSION

Acute ECG changes were common in type A AAD. Physicians taking care of patients with chest pain and acute ECG changes should consider the possibility of AAD before performing thrombolysis or percutaneous catheter intervention.

Electrocardiogram patterns in acute left main coronary artery occlusion

Acute coronary syndrome with subtotal occlusion of the left main coronary artery is rather frequently encountered in the catheterization laboratory, whereas survival to hospital admission of sudden total occlusion of the left main coronary artery is rare. The typical electrocardiographic (ECG) finding in cases with preserved flow through the left main is widespread ST-segment depression maximally in leads V4-V6 with inverted T waves and ST-segment elevation in lead aVR. In acute myocardial ischemia without (or with minor) myocardial necrosis, the ECG pattern is transient, whereas persistent ECG changes, usually without development of Q waves, are indicative of myocardial injury. In acute total left main occlusion, severe ischemia may be manifested in the ECG by life-threatening tachyarrhythmias, conduction disturbances, and ST-segment deviation. Because of the potential for life-saving therapeutic options by invasive therapy, the ECG markers of the serious condition should be recognized by the medical profession. Left main occlusion should be suspected in severely ill patients with widespread ST-segment depressions, especially in leads V4-V6 with inverted T waves or ST elevation involving the anterior precordial leads and the lateral extremity leads I and aVL. In addition, lead aVR ST elevation accompanied by either anterior ST elevation or widespread ST-segment depression may indicate left main occlusion.

Surgical Management of Coronary Malperfusion Due to Type A Aortic Dissection

BACKGROUND

Acute aortic dissection coexisting with coronary malperfusion is a relatively rare but fatal condition. Surgical treatment of these patients is to perform early coronary revascularization concomitant with aortic repair. We review our surgical results of a selected group of 14 patients with type A acute aortic dissection and coronary artery dissection.

METHODS

Between January 1993 and March 2005, 14 patients (10.2%) from a total of 136 consecutive patients with acute type A aortic dissection concomitant coronary dissection were treated by performing aortic repair and coronary artery bypass grafting. There were 11 men and 3 women (mean age, 56.7 +/- 8.4 years). The right coronary artery was involved in eight patients, the left in two patients, and both coronary arteries in four patients. At admission, nine patients had Q waves (64.2%), inferior in seven (50%) and anterior or lateral in two (14.2%).

RESULTS

Hospital mortality rate was 21.4% (3 of 14 patients). Of these, two patients could not be weaned from cardiopulmonary bypass, and one patient died of multiorgan failure in the intensive care unit.

CONCLUSIONS

Since acute type A aortic dissection with coronary involvement is associated with high mortality rate, immediate coronary artery bypass grafting and aortic repair is a safe and reliable approach to these challenging group of patients.

Aortic dissection associated with acute myocardial infarction and stroke found at autopsy

It is sometimes very difficult to diagnose dissecting aortic aneurysms in the early stage. We report an autopsy case in which an acute myocardial infarction and cerebral infarction simultaneously occurred and the symptoms were transiently ameliorated in a patient with an acute aortic dissection.

Aortic dissection with pseudo-aortic regurgitation and transient myocardial ischemia--a case report

Aortic dissection causes acute aortic regurgitation in one half to two thirds of cases, which is due, mainly, to dilatation of the aortic root. The unsupported intimal flap prolapse, which crosses the aortic valve, rarely produces aortic regurgitation. Moreover, transient myocardial ischemia rarely occurs by malperfusion, which might be due to compression of the ostium of the coronary artery by the false lumen or by the intimal flap. The authors had a rare case of aortic dissection with "pseudo-''aortic regurgitation; ie, regurgitation flow existed just in the area surrounding the intimal flap during diastole and produced transient myocardial ischemia. In this case, the swinging motion of the intimal flap through the aortic valve caused pseudoaortic regurgitation and transient myocardial ischemia, which should be repaired by emergency surgical procedure. Surgery was successful and saved the patient's life.

Simple and Useful Tests for Discriminating Between Acute Aortic Dissection of the Ascending Aorta and Acute Myocardial Infarction in the Emergency Setting

BACKGROUND

It is important to rapidly distinguish patients with acute aortic dissection of the ascending aorta (AADa) from those with acute myocardial infarction (AMI), because minimizing the time to initiation of reperfusion therapy leads to maximum benefits for AMI and erroneous reperfusion therapy for AADa can produce harmful outcomes. The aim of this study was to find a simple test to distinguish such patients.

METHODS AND RESULTS

Data were collected from 29 consecutive patients with AADa and 49 consecutive patients with AMI who were admitted within 4 h of the onset of symptoms. The D-dimer concentration and the ratio of the maximum upper mediastinal diameter to the maximum thoracic diameter on plain chest radiograph (M-ratio) in the emergency room were studied retrospectively. Setting the cutoff values of the D-dimer concentration and the M-ratio to 0.8 or 0.9 microg/ml and 0.309, respectively, gave a sensitivity of 93.1% and 93.1% for AADa, respectively, and a sensitivity of 91.8% and 85.7% for AMI, respectively.

CONCLUSIONS

The D-dimer value and the M-ratio, with appropriate cutoff values, have potential as tests that can be routinely used to exclude AADa patients from patients diagnosed with AMI prior to reperfusion therapy.

Coronary malperfusion due to type A aortic dissection: mechanism and surgical management

BACKGROUND

Coronary malperfusion associated with aortic dissection is relatively rare, but when it occurs, it is fatal to the patient. To salvage such moribund patients, aggressive coronary revascularization concomitant with aortic repair is essential. We review the surgical results and mechanism of malperfusion in a group of 12 patients with coronary malperfusion caused by type A aortic dissection, and we discuss our surgical approach.

METHODS

Between March 1990 and March 2003, 12 patients (6.1%) from a total of 196 consecutive patients with acute type A aortic dissection undergoing surgery suffered coronary malperfusion associated with the dissection. There were 4 men and 8 women (mean age, 60.8 +/- 8.3 years). Nine patients had acute myocardial infarction due to dissection before surgery, and 3 patients suffered coronary malperfusion after aortic declamping.

RESULTS

Hospital mortality rate was 33.3% (4 patients). The mortality rate was higher than that in patients without coronary malperfusion (33.3% vs. 8.2%, p = 0.019). Three patients could not be weaned from cardiopulmonary bypass, and 1 patient died of heart failure in the intensive care unit. Involved coronary arteries included the right coronary artery (8 patients), left coronary (2 patients), and both (2 patients). Mechanisms of coronary obstruction were compression (2 patients), coronary dissection (7 patients), and coronary disruption (3 patients). Coronary artery bypass grafting was performed concomitant with aortic repair.

CONCLUSIONS

Acute type A aortic dissection with coronary involvement is associated with high mortality rate, aggressive coronary revascularization and early aortic repair with simple techniques are necessary to salvage these critically ill patients.