Acute aortic intramural hematoma: an analysis from the International Registry of Acute Aortic Dissection.

BACKGROUND: Acute aortic intramural hematoma (IMH) is an important subgroup of aortic dissection, and controversy surrounds appropriate management. METHODS AND RESULTS: Patients with acute aortic syndromes in the International Registry of Acute Aortic Dissection (1996-2011) were evaluated to examine differences between patients (based on the initial imaging test) with IMH or classic dissection (AD). Of 2830 patients, 178 had IMH (64 type A [42%], 90 type B [58%], and 24 arch). Patients with IMH were older and presented with similar symptoms, such as severe pain. Patients with type A IMH were less likely to present with aortic regurgitation or pulse deficits and were more likely to have periaortic hematoma and pericardial effusion. Although type A IMH and AD were managed medically infrequently, type B IMH were more frequently treated medically. Overall in-hospital mortality was not statistically different for type A IMH compared to AD (26.6% versus 26.5%; P=0.998); type A IMH managed medically had significant mortality (40.0%), although less than classic AD (61.8%; P=0.195). Patients with type B IMH had a hospital mortality that was less but did not differ significantly (4.4% versus 11.1%; P=0.062) from classic AD. One-year mortality was not significantly different between AD and IMH. CONCLUSIONS: Acute IMH has similar presentation to classic AD but is more frequently complicated with pericardial effusions and periaortic hematoma. Patients with IMH have a mortality that does not differ statistically from those with classic AD. A small subgroup of type A IMH patients are managed medically and have a significant in-hospital mortality.

Comparative evaluation of left and right ventricular endomyocardial biopsy: differences in complication rate and diagnostic performance.

BACKGROUND: Endomyocardial biopsy (EMB) represents the gold standard for diagnosing myocarditis and nonischemic cardiomyopathies. This study focuses on the risk of complications and the respective diagnostic performance of left ventricular (LV), right ventricular (RV), or biventricular EMB in patients with suspected myocarditis and/or cardiomyopathy of unknown origin. METHODS AND RESULTS: In this 2-center study, 755 patients with clinically suspected myocarditis (n=481) and/or cardiomyopathy of nonischemic origin including those with infiltrative or connective tissue disease (n=274) underwent either selective LV-EMB (n=265; 35.1%), selective RV-EMB (n=133; 17.6%), or biventricular EMB (n=357; 47.3%) after coronary angiography and exclusion of significant coronary artery disease. Cardiovascular magnetic resonance, including late gadolinium enhancement, imaging was performed in 540 patients (71.5%). The major complication rate for LV-EMB was 0.64% and for RV-EMB, 0.82%. Considering postprocedural pericardial effusion that occurred after biventricular EMB, the minor complication rate for LV-EMB varied between 0.64% to 2.89% and for RV-EMB, between 2.24% and 5.10%. Diagnostic EMB results were achieved significantly more often in those patients who underwent biventricular EMBs (79.3%) compared to those who underwent either selective LV-EMB or selective RV-EMB (67.3%; P<0.001). In patients with biventricular EMB, myocarditis was diagnosed in LV-EMB samples in 18.7% and in RV-EMB samples in 7.9% (P=0.002) , and it was diagnosed in both ventricles in 73.4%. There were no differences in the number of positive LV-EMB, RV-EMB, or LV- and RV-EMB findings when related to the site of cardiovascular magnetic resonance-based late gadolinium enhancement. CONCLUSIONS: Both LV-EMB and RV-EMB are safe procedures if performed by experienced interventionalists. The diagnostic yield of EMB may be optimized when samples from both ventricles are available. Preferential biopsy in regions showing late gadolinium enhancement on cardiovascular magnetic resonance does not increase the number of positive diagnoses of myocarditis.

The role of preoperative coronary angiography in the setting of type A acute aortic dissection: insights from the International Registry of Acute Aortic Dissection.

BACKGROUND: Performing preoperative coronary angiography (CA) before surgical repair of a type A acute aortic dissection (TA-AAD) remains controversial. Although the information provided by CA may be useful in planning the surgical approach, the potential delay to surgery and complications of CA may confer added risk of death before definitive repair of the aorta. METHODS: We analyzed 1,343 patients from January 27, 1996, to May 3, 2010, with TA-AAD from the International Registry of Acute Aortic Dissection who underwent surgical or endovascular repair during the index hospitalization, with (n = 156) or without (n = 1,187) preoperative CA. The main outcomes measured were in-hospital complications and in-hospital and long-term mortality. RESULTS: Patients who underwent preoperative CA were more likely to have a history of atherosclerosis and present with electrocardiographic signs of myocardial ischemia/infarction. In the preoperative CA group, significant delays from the onset of symptoms to the time of surgery occurred. In-hospital postoperative complications and mortality rates were largely similar between the 2 groups. On multivariable logistic regression analysis, preoperative CA had no significant effect on in-hospital risk-adjusted mortality when compared to the validated International Registry of Acute Aortic Dissection risk score. Long-term mortality was similar between patients receiving preoperative CA and those who did not; long-term rehospitalization rates were higher, although largely insignificantly, among preoperative CA recipients through 5 years of follow-up. CONCLUSIONS: Preoperative CA is infrequently performed on patients with TA-AAD, except, occasionally, on patients at high risk for myocardial ischemia. When performed, preoperative CA was not associated with any significant changes in in-hospital and long-term mortality.

Diagnostic synergy of non-invasive cardiovascular magnetic resonance and invasive endomyocardial biopsy in troponin-positive patients without coronary artery disease.

AIMS: Only few data are available regarding a direct comparison of both non-invasive CMR and invasive EMB with respect to conformity of procedure-derived diagnoses in the same patients. The aim of this study was to elucidate the diagnostic performance of non-invasive cardiovascular magnetic resonance imaging (CMR) and endomyocardial biopsy (EMB) in patients with troponin-I (TnI) positive acute chest pain in the absence of significant coronary artery disease (CAD). METHODS AND RESULTS: One thousand one hundred and seventy-four consecutive patients who were admitted with TnI-positive acute chest pain between March 2004 and July 2007 underwent coronary angiography. In 1012 patients (86%), significant CAD (stenosis >50%) was detected as underlying reason for the acute chest pain. In 82 out of the remaining 162 patients without significant CAD, further workup was performed including both CMR and EMB. Cardiovascular magnetic resonance imaging alone enabled a diagnosis in 66/82 (80%) and EMB alone in 72/82 (88%) patients (P = 0.31). Myocarditis was the most frequent diagnosis by both CMR and EMB in this cohort and was detected with a higher frequency by EMB (58 vs. 81%; P < 0.001). With the combined approach comprising CMR and EMB, a final diagnosis could be established applying the 'Believe-The-Positive-Rule' in 78/82 patients (95%). This combined approach turned out to yield more diagnoses than either CMR (P < 0.001) or EMB (P = 0.03) as single techniques, respectively. Comparison of diagnostic CMR procedures with the corresponding diagnostic EMBs demonstrated a substantial match of diagnoses (kappa = 0.70). CONCLUSION: Cardiovascular magnetic resonance imaging and EMB have good diagnostic performances as single techniques in patients with TnI-positive acute chest pain in the absence of CAD. The combined application of CMR and EMB yields a considerable diagnostic synergy by overcoming some limitations of CMR and EMB as individually applied techniques.

Pulse pressure and type A acute aortic dissection in-hospital outcomes (from the International Registry of Acute Aortic Dissection).

Little is known about the relation between type A acute aortic dissection (TAAAD) and pulse pressure (PP), defined as the difference between systolic and diastolic blood pressure. In this study, we explored the association between PP and presentation, complications, and outcomes of patients with TAAAD. PP at hospital presentation was used to divide 1,960 patients with noniatrogenic TAAAD into quartiles: narrowed (≤39 mm Hg, n=430), normal (40 to 56 mm Hg, n=554), mildly elevated (57 to 75 mm Hg, n=490), and markedly elevated (≥76 mm Hg, n=486). Variables relating to index presentation and in-hospital outcomes were analyzed. Patients with TAAAD in the narrowed PP quartiles were frequently older and Caucasian, whereas patients with markedly elevated PPs tended to be male and have a history of hypertension. Patients who demonstrated abdominal vessel involvement more commonly demonstrated elevated PPs, whereas patients with narrowed PPs were more likely to have periaortic hematoma and/or pericardial effusion. Narrowed PPs were also correlated with greater incidences of hypotension, cardiac tamponade, and mortality. Patients with TAAAD who were managed with endovascular and hybrid procedures and those with renal failure tended to have markedly elevated PPs. No difference in aortic regurgitation at presentation was noted among groups. In conclusion, patients with TAAAD in the third PP quartile had better in-hospital outcomes than patients in the lowest quartile. Patients with narrowed PPs experienced more cardiac complications, particularly cardiac tamponade, whereas those with markedly elevated PPs were more likely to have abdominal aortic involvement. Presenting PP offers a clue to different manifestations of acute aortic dissection that may facilitate initial triage and care.

Severe hyperphosphatemia in a patient with chronic kidney disease and multiple myeloma-to strengthen the case toward renal replacement therapy?

KEY CLINICAL MESSAGE: We report a patient with multiple myeloma and chronic kidney disease who presented with severe hyperphosphatemia in the outpatient clinic without any related symptoms. Initial differential diagnosis: Tumor lysis syndrome or chronic kidney disease. Further work-up revealed pseudohyperphosphatemia. In general, treatment is not necessary if the true phosphate level is within the reference range and the patient is asymptomatic.

Transcatheter aortic valve replacement: does kidney function affect outcome?

BACKGROUND: Chronic kidney disease is a significant risk factor for mortality as well as acute kidney injury in cardiac surgery. The impact of contrast agent application on outcome is not well described in patients undergoing transcatheter aortic valve implantation. METHODS: We analyzed data of 270 patients who underwent transcatheter aortic valve implantation (TAVI) between September 2008 and March 2012. Acute kidney injury was defined according to modified risk, injury, failure, loss and end-stage renal failure criteria. Patients on chronic hemodialysis were analyzed separately (n = 15). In 129 (47.8%) patients chronic kidney disease was apparent preoperatively. On average, 83.7 (± 32.4) mL of contrast agent were used per patient. RESULTS: Postoperatively, 41 patients (15.2%) developed acute kidney injury. In 19 patients (7.1%) transient renal replacement therapy was necessary; no chronic hemodialysis was required. Thirty-day-mortality did not differ between patients with or without chronic kidney disease (7.0% vs 7.1%, p = 0.97). Additionally, chronic kidney disease had no influence on the incidence of postoperative acute kidney injury (12.8% vs 20.2%, p = 0.07) or postoperative hemodialysis (5.0% vs 10.5%, p = 0.08). No correlation between the amount of contrast agent applied and the incidence of acute kidney injury could be verified (p = 0.57). CONCLUSIONS: Preoperative chronic kidney disease does not increase the risk of mortality and acute kidney injury after transcatheter aortic valve implantation. Acute kidney injury after TAVI is associated with an elevated risk of mortality. The amount of contrast agent applied intra-procedurally does not affect the risk of acute kidney injury.

Outcome of patients after emergency conversion from transcatheter aortic valve implantation to surgery.

AIMS: To evaluate: 1) the causes of emergency conversion from transcatheter aortic valve implantation (TAVI) to surgery, 2) procedural settings, and 3) short-term outcome of converted patients. METHODS AND RESULTS: The prospective German TAVI registry was used to identify patients who underwent bail-out surgery during TAVI. Additionally, standardised questionnaires were developed and used to assess more detailed periprocedural and postprocedural data. Emergency conversion from TAVI to open cardiac surgery was required in 24 of 1,975 patients (1.2%). Primary conversion causes were aorto-valvular complications (i.e., aortic annulus rupture, aortic perforation, or thoracic aortic dissection). This was followed by prosthesis embolisation, myocardial perforation, severe aortic regurgitation, and coronary obstructions. The mean time interval between abortions of TAVI to surgery was 19 minutes (SD ± 17 min, range 5-80 min). Four of 24 patients (16.7%) died during the initial surgery, seven of 24 (29.2%) within the first 72 hours and the 30-day mortality was 45.8%. The highest mortality was observed in patients with aortic perforation or dissection (4/5, 80%). Mortality rates for other entities were: prosthesis embolisation 40% (2/5), myocardial perforation 50% (2/4), annulus rupture 67% (2/3), severe aortic regurgitation 33% (1/3), and coronary impairment 0% (0/3). CONCLUSIONS: Emergency conversion from TAVI to surgery is a rare event carrying a mortality of around 45% after 30 days. Outcome of converted patients with prior injury of aortic, aorto-valvular, or myocardial tissue during TAVI was poor, whereas patients with severe aortic regurgitation and those with coronary complications had a more favourable outcome after 30 days. Collected procedural and outcome data demand on-site cardiac surgery as a prerequisite for TAVI and constant process optimisation efforts regarding such emergency scenarios.

Patients with type A acute aortic dissection presenting with major brain injury: should we operate on them?

OBJECTIVES: The management strategy remains controversial for patients presenting with type A acute aortic dissection with cerebrovascular accident or coma. The present study aimed to help guide surgeons treating these high-risk patients. METHODS: Of 1873 patients with type A acute aortic dissection enrolled in the International Registry for Acute Dissection, 87 (4.7%) presented with cerebrovascular accident and 54 (2.9%) with coma. The hospital and 5-year results were stratified by the presence and type of brain injury (no injury vs stroke vs coma) and management type (medical vs surgical). Independent predictors of short- and mid-term survival were identified. RESULTS: Presentation with shock, hypotension, or tamponade (46.8% vs 25.2%; P < .001) and arch vessel involvement (55.0% vs 36.1%; P < .001) was more likely in patients with brain injury. Surgical management was avoided more often in patients with coma (33.3%) or cerebrovascular accident (24.1%) than in those without brain injury (11.1%; P < .001). The overall hospital mortality was 22.7% without brain injury, 40.2% with cerebrovascular accident, and 63.0% with coma (P < .001). Mortality varied among the management types for both cerebrovascular accident (76.2% medical vs 27.0% surgical; P < .001) and coma (100% medical vs 44.4% surgical; P < .001). Postoperatively, cerebrovascular accident and coma resolved in 84.3% and 78.8% of cases, respectively. On logistic regression analysis, surgery was protective against mortality in patients presenting with brain injury (odds ratio 0.058; P < .001). The 5-year survival of patients presenting with cerebrovascular accident and coma was 23.8% and 0% after medical management versus 67.1% and 57.1% after surgery (log rank, P < .001), respectively. CONCLUSIONS: Brain injury at presentation adversely affects hospital survival of patients with type A acute aortic dissection. In the present observational study, the patients selected to undergo surgery demonstrated improved late survival and frequent reversal of neurologic deficits.

Transcatheter aortic valve implantation in patients with and without concomitant coronary artery disease: comparison of characteristics and early outcome in the German multicenter TAVI registry.

OBJECTIVE: To examine the prevalence and impact of concomitant coronary artery disease (CAD) on short-term outcome after transcatheter aortic valve implantation (TAVI). BACKGROUND: The prevalence of CAD in patients undergoing surgical aortic valve replacement is estimated at 30-50 % and its presence increases procedural risk. The prevalence and impact of CAD on outcome after TAVI are not well defined. METHODS: We analyzed 1,382 patients enrolled in the German TAVI registry; the majority (81 %) received the Medtronic CoreValve. The presence of coronary lesions with ≥50 % stenosis on pre-TAVI angiography defined the existence of concomitant CAD. RESULTS: 859 patients (62.2 %) had concomitant CAD, of which 534 (62.3 %) had multi-vessel and 83 (9.7 %) left main disease. Patients with CAD were younger (81.5 ± 6.1 vs. 82.1 ± 6.3 years, p < 0.05), more commonly males (49.4 vs. 30.0 %, p < 0.0001) and diabetics (36.9 vs. 31.2 %, p < 0.05), and had a worse Canadian Cardiovascular Society angina class at baseline compared to patients with no CAD. During TAVI patients with CAD more often required additional coronary intervention and had longer procedures, but procedural success rates were similar (97.1 vs. 97.7 %). Crude in-hospital mortality was higher in patients with CAD (10.0 vs. 5.5 %, OR 1.90, 95 % CI 1.23-2.93), but this was not significant after adjustment for confounders (adjusted OR 1.41, 95 % CI 0.85-2.33). Both groups had significant improvement in 30-day symptoms and quality of life. CONCLUSION: The prevalence of CAD in contemporary TAVI patients is high. Its presence characterizes a high-risk population and is associated with increased crude short-term mortality, largely explained by co-morbidities, but does not limit functional improvement after TAVI.

Age-stratified baseline and outcome characteristics of patients undergoing transcatheter aortic valve implantation: results from the German multicenter registry.

OBJECTIVES: To analyze age dependencies in patients currently undergoing transcatheter aortic valve implantation (TAVI) based on the German TAVI registry. BACKGROUND: TAVI is a promising, less invasive treatment option for surgical high-risk patients with symptomatic aortic valve stenosis, with the majority being octogenarians treated so far. Younger patients with significant co-morbidities are now increasingly considered for this procedure, but little is known about this population. METHODS: The German TAVI registry is an ongoing non-randomized national multicenter study. Consecutive patients who underwent TAVI between January 2009 and June 2010 were included in this analysis. We compared baseline characteristics, procedural characteristics, and short-term clinical outcome up to 30-day follow-up. RESULTS: A total of 1386 patients were divided into 4 roughly equally-sized groups: group A, n = 347, mean age 73.4 ± 4.5 years; group B, n = 350, mean age 80.6 ± 1.1 years; group C, n = 382, mean age 84.5 ± 1.1 years; and group D, n = 312, mean age 88.9 ± 2.2 years. Patient characteristics varied significantly, with more co-morbidities in younger patients. Technical success rates were similar in all groups (96.6%-97.7%; P=NS). 30-day major adverse event rates were similar with an all-cause mortality rate of 7.2% (A), 7.1% (B), 9.7% (C) and 8.7% (D; P=NS). Postprocedural improvement of both New York Heart Association and self-reported health status was significant in all groups, with significantly better improvements in the categories 'mobility' and 'ability for self-care' in younger patients. CONCLUSION: TAVI appears to be similarly safe and effective across different age groups with currently applied enrollment criteria, but younger patients present with significantly more co-morbidities. All patient populations experience functional improvements, but this is particularly pronounced for younger patients.

Aortic expansion after acute type B aortic dissection.

BACKGROUND: A considerable number of patients with acute type B aortic dissection (ABAD) treated with medical management alone will exhibit aortic enlargement during follow-up, which could lead to aortic aneurysm and rupture. The purpose of this study was to investigate predictors of aortic expansion among ABAD patients enrolled in the International Registry of Acute Aortic Dissection. METHODS: We analyzed 191 ABAD patients treated with medical therapy alone enrolled in the registry between 1996 and 2010, with available descending aortic diameter measurements at admission and during follow-up. The annual aortic expansion rate was calculated for all patients, and multivariate regression analysis was used to investigate factors affecting the expansion rate. RESULTS: Aortic expansion was observed in 59% of ABAD patients; mean expansion rate was 1.7±7 mm/y. In multivariate analysis, white race (regression coefficient [RC], 4.6; 95% confidence interval [CI], 1.4 to 7.7) and an initial aortic diameter less than 4.0 cm (RC, 6.3; 95% CI, 4.0 to 8.6) were associated with increased aortic expansion. Female sex (RC, -3.8; 95% CI, -6.1 to -1.4), intramural hematoma (RC, -3.8; 95% CI, -6.5 to -1.1), and use of calcium-channel blockers (RC, -3.8; 95% CI, -6.2 to -1.3) were associated with decreased aortic expansion. CONCLUSIONS: White race and a small initial aortic diameter were associated with increased aortic expansion during follow-up, and decreased aortic expansion was observed among women, patients with intramural hematoma, and those on calcium-channel blockers. These data raise the possibility that the use of calcium-channel blockers after ABAD may reduce the rate of aortic expansion, and therefore further investigation is warranted.

3-year follow-up of patients with coronary artery spasm as cause of acute coronary syndrome: the CASPAR (coronary artery spasm in patients with acute coronary syndrome) study follow-up.

OBJECTIVES: We sought to determine the prognosis of patients with acute coronary syndrome without culprit lesion and proof of coronary spasm during 3 years of follow-up. BACKGROUND: Coronary artery spasm has been identified as an alternative cause for acute coronary syndrome (ACS) in patients without culprit lesion. In the CASPAR (Coronary Artery Spasm as a Frequent Cause for Acute Coronary Syndrome) study, we recently showed that ∼50% of ACS patients without culprit lesion, in whom intracoronary acetylcholine provocation was performed, had coronary spasm. However, data on prognosis in these patients are sparse. METHODS: After 3 years of follow-up, data regarding the following end points were obtained: death (cardiac and noncardiac), nonfatal myocardial infarction, and recurrent angina leading to repeated coronary angiography. The analysis focused on patients with a culprit lesion (n = 270) and patients without a culprit lesion (n = 76) but with acetylcholine provocation (total n = 346). RESULTS: In patients without culprit lesion, there was no cardiac death or nonfatal myocardial infarction during follow-up; 1 patient died due to a noncardiac cause. However, 38 of 76 patients reported persistent angina requiring repeated angiography in 3 cases (3.9%). Thirty of 270 patients with culprit lesion died due to a cardiac cause (11.1%) and 13 due to a noncardiac cause (4.8%). Eleven patients had nonfatal myocardial infarction (4.1%) and 27 repeated angiography due to persistent or recurrent angina (10%). Patients with a culprit lesion had a higher mortality and more coronary events compared with those without (p < 0.0005, log-rank test). CONCLUSIONS: ACS patients without culprit lesion and proof of coronary spasm have an excellent prognosis for survival and coronary events after 3 years compared with patients with obstructive ACS. However, persistent angina represents a challenging problem in these patients, leading in some cases to repeated coronary angiography.

Diagnostic value of perfusion cardiovascular magnetic resonance in patients with angina pectoris but normal coronary angiograms assessed by intracoronary acetylcholine testing.

BACKGROUND: Perfusion cardiovascular magnetic resonance (CMR) has a high sensitivity for the detection of significant coronary artery disease (CAD). However, the specificity of this method is lower than its sensitivity. The reason for this observation is hitherto unclear and has been either explained by 'false-positive' results or by microvascular dysfunction in patients without CAD. OBJECTIVE: To evaluate whether pathological myocardial perfusion-CMR imaging in symptomatic patients without significant CAD is associated with coronary epicardial or microvascular dysfunction. METHODS: In this retrospective study, 42 patients who presented with unstable angina pectoris underwent (a) an adenosine-stress perfusion-CMR study; (b) coronary angiography; (c) intracoronary acetylcholine (ACh) testing following coronary angiography with exclusion of significant CAD. The CMR protocol comprised cine imaging followed by adenosine first-pass perfusion imaging and late gadolinium enhancement-CMR. Diagnostic left ventriculography and multiplane coronary angiography were performed before intracoronary ACh testing. RESULTS: An adenosine-induced, reversible subendocardial perfusion defect was detected in 22/42 patients (52%) without significant CAD. Coronary epicardial vasospasm was detected in 10/42 patients (24%) while microvascular dysfunction was found in 20/42 patients (48%). Patients with a reversible stress-induced perfusion defect had significantly more often a pathological coronary epicardial or microvascular vasoreaction (20/22; 91%) during intracoronary ACh testing than those without a perfusion defect (10/20; 50%; p<0.01). Univariate correlation analyses revealed a substantial association between a pathological ACh-testing result and a perfusion defect in the antecedent CMR study (r= +0.45; p<0.01). CONCLUSIONS: Reversible perfusion defects depicted by perfusion-CMR in patients without significant CAD are mostly due to coronary epicardial or microvascular dysfunction, and correct interpretation of such perfusion-CMR results may enable targeted treatment.

Coronary artery spasm as a frequent cause of acute coronary syndrome: The CASPAR (Coronary Artery Spasm in Patients With Acute Coronary Syndrome) Study.

OBJECTIVES: This study was conducted to clarify the incidence of coronary spasm in emergency patients with suspected acute coronary syndrome (ACS) and acute chest pain at rest. BACKGROUND: Chest pain at rest is a frequent symptom in the emergency room. Acute coronary syndrome is suspected in patients with elevation of cardiac markers, ischemic electrocardiographic changes, or simply typical clinical symptoms of unstable (usually resting) angina. However, of all patients with suspected ACS who undergo coronary angiography, up to 30% have nonobstructed coronary arteries. We sought to clarify how many of these patients suffer from coronary spasm as a possible cause of their chest pain. METHODS: In a prospective study from June to December 2006, all patients with suspected ACS who underwent coronary angiography and had no culprit lesion underwent intracoronary provocation with acetylcholine. The ACH testing was considered positive at a vasoconstriction of >/=75% relative to the diameter after intracoronary nitroglycerine when the initially reported symptoms could be reproduced. RESULTS: Of 488 consecutive patients, 138 had no culprit lesion (28%). Twenty-two were found to have another diagnosis. The ACH testing was performed in 86 of the remaining 116 patients. In 42 patients, coronary spasm was verified (49%). CONCLUSIONS: Every fourth patient with ACS had no culprit lesion. Coronary spasm could be documented in nearly 50% of the patients tested by ACH. Coronary spasm is a frequent cause of ACS and should regularly be considered as a differential diagnosis.