Comparison of the Utility of Transthoracic Echocardiographic and Cardiac Magnetic Resonance Imaging in Patients Presenting with Troponin Positive Chest Pain with Unobstructed Coronary Arteries

Results: At baseline, there is no significant difference between TAVI and SAVR groups in terms of aortic valve (AV) peak velocity (Vmax ), AV mean pressure gradient (PG) and DI (4.1 ± 0.6 m/s vs. 4.2 ± 0.6 m/s; 41.0 ± 11.3 mmHg vs. 45.2 ± 14.5 mmHg; 0.21 ± 0.06 vs. 0.23 ± 0.06; respectively; p = 0.33). Post-procedurally, the TAVI cohort has lower AV Vmax and mean PG (2.2 ± 0.5 m/s vs. 2.75 ± 0.6 m/s; 11.2 ± 5.5 mmHg vs. 17.7 ± 8.1 mmHg respectively; p = < 0.001) whilst the DI is higher (0.49 ± 0.15 vs. 0.43 ± 0.15; p = 0.01). In patients with matched preand post-procedure Doppler measurements, the degree of change in Vmax (␦Vmax ) and DI (␦DI) is also larger in the TAVI group (p = 0.02). Irrespective of prosthesis size, SAVR group has more possible patient–prosthesis mismatches (40.7% vs. 23.1%; p = 0.05). TAVI is associated with higher incidence of peri-prosthesis leaks (n = 29 vs. n = 4), however majority of which are mild in severity (46.3% mild; 5.6% mild-moderate; 1.9% moderate; 0% severe). Conclusion: TAVI is associated with a more favourable haemodynamic outcome, at the cost of higher incidence of peri-prosthesis leaks, majority of which are mild in nature. doi:10.1016/j.hlc.2011.05.409 406 Comparison of the Utility of Transthoracic Echocardiographic and Cardiac Magnetic Resonance Imaging in Patients Presenting with Troponin Positive Chest Pain with Unobstructed Coronary Arteries M. Habibian 1,∗ , S. Luis 1,∗ , C. Luis 2 , A. Courtney 1 , C. Hamilton-Craig 1,3 , W. Strugnell 1 , M. Hansen 1 , R. Slaughter 1 , O. Raffel 1 1 Cardiac

Imaging Research Group, The Prince Charles Hospital, Brisbane, Australia 2 University of New South Wales, Sydney, Australia 3 University of Queensland, Brisbane, Australia Introduction: Establishing a causative diagnosis in patients with troponin positive acute coronary syndromes (ACS) who have no identifiable culprit lesion at angiography is a common clinical challenge. We examine and compare the role of transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR) in these patients. Methods: TTE and CMR (1.5 T) were performed in consecutive patients presenting with a troponin positive ACS, without obvious culprit coronary lesions at angiography. All patients underwent CMR with cine-SSFP, T2-weighted, and late gadolinium enhancement imaging. Results: Seventy-four patients (mean age 54.4, male sex 47.3%) were included. TTE and CMR were performed within a mean duration of 4.5 and 4.3 days from presentation, respectively. Twenty-five patients had a CMR diagnosis of myocardial infarction, but only 13 (52%) had regional wall motion abnormalities (RWMA) detected on TTE. Seventeen had Tako-tsubo cardiomyopathy, with 16 (94.1%) having concordant RWMA on TTE. Seventeen had a CMR diagnosis of myocarditis, with RWMA identified on TTE in 13 (75.5%). Nine patients had no detectable abnormality on CMR, with two (22.2%) having

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RWMA on TTE. The remaining subjects consisted of three hypertrophic cardiomyopathies, two idiopathic dilated cardiomyopathies and one pulmonary embolism: which were successfully diagnosed on both imaging modalities. Conclusions: In the investigation of patients with troponin positive ACS and unobstructed coronaries, the use of TTE did not confer any additional diagnostic value when used in addition to CMR. The ability of CMR to determine myocardial tissue characteristics appears to achieve greater diagnostic certainty when compared to TTE. doi:10.1016/j.hlc.2011.05.410 407 Computed Tomography Guided Pericardiocentesis in Adults: A Single Centre Experience of 44 Procedures F. Syed ∗ , R. Slaughter, C. Tjahjadi ∗ , M. Hansen, O. Raffel Cardiac Imaging Research Group, The Prince Charles Hospital, Australia Background: Both X-ray fluoroscopy and echocardiography guided pericardiocentesis may be associated with a major complication rate of 1.2–4%. Additionally they do not allow direct visualisation of needle advancement and are of limited utility in effusions that are loculated or restricted to certain locations such as around the right atrium. Computed Tomography (CT) guided pericardiocentesis can overcome many of these limitations. Methods: Consecutive adult patients that underwent CT guided pericardiocentesis at our institution were retrospectively analysed. Clinical characteristics, echocardiographic findings, and procedural outcomes were assessed. Results: Forty four procedures from 40 patients (mean age 56, male sex 52.5%) were included. Two patients had previously failed fluoroscopy and echocardiography guided attempts. The aetiology of the effusions were post-operative 17 (38.6%), idiopathic 13 (29.5%), malignancy-associated 7 (15.9%), heart failure 2 (15.9%) and other causes 5 (11.4%; 2 chylous, 3 related to autoimmune disorder). The mean size of effusion on echocardiography was 31 mm and 28 (63.6%) had features of tamponade. Location of the effusion was circumferential in 18.2%, right ventricular 29.5%, left ventricular 34.1%, apical in 2.3% and localised around the right atrium in 13.6%. The procedural success rate for drainage of the effusion was 95.5% with only 2 (4.5%) minor complications (small pneumothrax not requiring intervention) and no major complications or deaths. Conclusion: CT-guided pericardiocentesis is a safe and effective procedure for the routine drainage of pericardial effusions of varying aetiology. Its unique ability to directly visualise needle entry makes particularly suitable for effusions in locations which are difficult to access with other techniques. doi:10.1016/j.hlc.2011.05.411

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Heart, Lung and Circulation 2011;20S:S156–S251