Comparing Cardiopulmonary Exercise Testing with Standard Exercise Treadmill Testing in Chronic Mixed Heart Valve Disease

ciation with recognized risk factors (associated PAH) (OR 3.8; p = 0.01) and PH due to pulmonary and/or LHD (OR 7.8; p < 0.0001) were more likely to have LA dilatation when compared to patients with idiopathic PAH or thromboembolic PH. Conclusions: LA enlargement was uncommon in patients in sinus rhythm with idiopathic and thromboembolic PH. In the determination of PH etiology, LAV may be useful as a non-invasive indicator of LHD. doi:10.1016/j.hlc.2007.06.145 141 Atrial Fibrillation: Trends in Management O.S. Adera ∗ , J.J. Lleitch Department of Cardiology, John Hunter Hospital, NSW, Australia Atrial fibrillation is a common reason for hospital admission. There is evidence for long-term warfarin for stroke prevention. However, there is changing trends in the preferred strategy of symptom control. We assessed the preferred management strategies in patients admitted to our institution with the primary diagnosis of atrial fibrillation in 2002 and 2004. Methods: we analysed retrospective data of 388 patients with the principal diagnosis of atrial fibrillation in 2002 and 2004. Data on the management strategy and co-morbities were taken from the patients’ medical records. Results: in 2002, 53% of the patients had rhythm control whereas 56% of the patients had rate control in 2004. Beta blockers were the most preferred for rate control while ccbs the least. Rhythm control using amiodarone declined from 43% in 2002 to 22% in 2004. About 60% were over 65 and less than 10% were under 44 years. Hypertension and chronic heart failure were the most common associated cardiovascular co-morbidities. Atrial fibrillation was present in 20% and 15% in those admitted with heart failure in 2002 and 2004 respectively. Chronic heart failure was present in 30% and 25% in those admitted with atrial fibrillation in 2002 and 2004 respectively. Obesity and sleep apnea were probably significant in the young. Conclusion: rate control of atrial fibrillation using beta blockers or digoxin and long term anticoagulation was the preferable strategy in 2004 with marked decline in amiodarone use. Age, hypertension and chronic heart failure are closely associated with atrial fibrillation. doi:10.1016/j.hlc.2007.06.146

Abstracts

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142 Prevention of Contrast Induced Nephropathy Using Rotational Coronary Angiography A. Alasady ∗ , A. Farshid, Craig Lawlor The Canberra Hospital, Yamba Drive, Garran, ACT, Australia Background: The incidence of contrast-induced nephropathy (CIN) in renal patients (eGFR < 60) after cardiac catheterisation is 5–38%. Rotational coronary angiography is a new X-ray acquisition technique, which enables rotation of a flat panel imaging system around the patient during injection of contrast, thereby minimising contrast and radiation dose compared with conventional coronary angiography. Our aim was to assess the feasibility and safety of rotational coronary angiography in renal patients (eGFR < 60 ml/min) and to estimate the incidence of CIN in this population. Methods: We performed rotational coronary angiography in 94 patients, 27 of whom had an eGFR less than 60 ml/min. Femoral artery access was used in all patients. Serum creatinine was measured before and 48–96 h after the procedure. Results: Mean age was 73.3 years in renal patients and 60.2 years in others (p < 0.0001). Mean contrast volume (excluding ventriculography) was 37.6 mL for renal patients and 36 mL for other patients (p = NS). The screening time was 4.5 min for renal patients and 4.1 min for other patients (p = NS). In renal patients the mean serum creatinine was 155.5 ␮mol/L before the procedure and 151.3 ␮mol/L after the procedure. Seven patients had an eGFR ≤ 30 mL/min at baseline. There were no patients who suffered a significant rise in serum creatinine, defined as a 25% increase above the baseline value. Image quality was good in all patients and comparable to conventional angiography. Conclusion: Rotational coronary angiography is feasible and safe in patients with renal impairment and associated with a low risk of contrast-induced nephropathy. doi:10.1016/j.hlc.2007.06.147 143 Comparing Cardiopulmonary Exercise Testing with Standard Exercise Treadmill Testing in Chronic Mixed Heart Valve Disease N. Bissessor 1,∗ , R. Stewart 1 , I. Zeng 1 , K. Ellyet 2 , J. Kolbe 2 , A. Kerr 3 Research Unit, New Zealand; 2 Auckland City Hospital, Auckland, New Zealand; 3 Middlemore Hospital, Auckland, New Zealand 1 Greenlane

Background: Cardiopulmonary Exercise testing (CPEX) is used to directly quantify exercise capacity by means of measuring peak oxygen consumption (pVO2). Exercise testing is used to establish reduced effort tolerance and detect symptoms in patients with valvular heart disease. The standard exercise treadmill test (ETT) estimates work performed by calculating the MET capacity (1 MET = 3.5 ml/kg/min).

ABSTRACTS

Heart, Lung and Circulation 2007;16:S1–S201

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Abstracts

Heart, Lung and Circulation 2007;16:S1–S201

ABSTRACTS

Purpose: (1) To establish if MET capacity from ETT correlates with pVO2 from CPEX. (2) To compare how parameters of cardiac and respiratory function correlate with MET capacity and pVO2 measurements in mixed valvular heart disease. Method: Patients (n = 45; NYHA class I (17), Class II (28)) with moderate-severe valvular lesions by echocardiographic criteria underwent a symptom-limited ETT as well as spirometry and pVO2 measurements from formal CPEX with gas analysis.. Results: Mean pVO2 = 17.4(±8.1) ml/kg/min; Mean METs = 6.6(±3.2) = 23.1(±11.5) ml/kg/min. Correlation r = 0.71 p < 0.0001. Conclusion: There is good correlation between the peak exercise capacity determined by standard ETT and formal CPEX. The MET capacity is a useful guide to estimate peak cardiovascular aerobic capacity and detect poor effort tolerance in chronic mixed valvular heart disease.

the lowest, middle and highest tertile of %pVO2 (predicted for age, gender, BMI). In multivariate analysis LogNtproBnp (beta = −9.3, se = 1.9, p < 0.0001) and lean body weight (beta = 0.59, se = 0.22, p = 0.01) were dominant independent predictors of pVO2. NtproBNP 84pmol/l had 77% sensitivity and 70% specificity to predict pV02 < 60%, AUC = 0.80. Conclusion: Resting NtproBnp is the best predictor of pVO2 while symptoms are a less reliable guide. Impaired respiratory function and lower lean body weight, possibly due to deconditioning, also contribute to impaired pVO2 in severe MVD. doi:10.1016/j.hlc.2007.06.149 145 Device Implantation Procedures in Anticoagulated Patients are Safe Tau Boga ∗ , Nigel Lever, Keith Tiong, Scott Harding

METs pVo2

*

EF

LA

%FVC

% FEV1

%DLCO

LBW

NtproBnp

0.13

−0.25

0.44**

0.42**

0.30*

0.16

−0.56**

−0.28

0.52**

0.53**

0.44**

0.46**

−0.63**

0.28

Association(r) between functional parameters and METs or pVO2. p < 0.05 ** p < 0.01.

doi:10.1016/j.hlc.2007.06.148 144 Natriuretic Peptides Predict Peak Oxygen Consumption in Patients with Chronic Mixed/Multiple Heart Valve Disease (MVD) N. Bissessor 1,∗ , R. Stewart 1 , I. Zeng 1 , K. Ellyet 2 , J. Kolbe 2 , A. Kerr 3 1 Greenlane Research Unit, New Zealand; 2 Auckland Hospital, Auckland, New Zealand; 3 Middlemore Hospital, Auckland, New Zealand

Background: Impaired functional capacity is an important determinant of the decision to operate, prognosis and surgical risk in patients with MVD. Assessing the presence and cause of functional limitations may be difficult in individual patients. Methods: Factors associated with impaired peak oxygen consumption (pVO2 ) on formal cardiopulmonary exercise testing with gas analysis were assessed in 45 patients with moderate-severe stenosis or regurgitation of the heart valves. Results: Cohort: Mixed mitral valve disease (n = 15), Mixed aortic valve disease (n = 2), AS/MR (n = 13), and AS/MR/TR (n = 15). Factors are presented (Table 1) for patients in Table 1. Factors associated with pVO2 (n = 15/tertile) number (%), mean ± (S.D.) %pVO2 Symptomatic Valve severity score Lean body weight (kg) %Predicted FVC NtproBnp (pmol/l)

22–47% 12 (75%) 10.1(2.3) 45 (13) 74.9(14.1) 158 (325)

48–67% 10 (71%) 8.9 (2.3) 52 (9) 83.4 (14.3) 110 (200)

>67% 6 (40%) 8.1(1.9) 56 (11) 94.7(19.7) 28 (26)

P 0.09 0.04 0.03 0.007 <0.0001

Cardiology Department, Wellington Hospital, Wellington, and Green Lane Cardiovascular Service, Auckland Hospital, New Zealand Introduction: Anticoagulation is considered a relative contraindication for device implantation/replacement procedures. We performed this study to evaluate the impact of various levels of anticoagulation at the time of device procedures on complication rates. Methods: Between 2001 and 2006, 1240 permanent pacemaker (PPM) or cardioverter/defibrillator (ICD) procedures were performed at our institution. Demographic and procedural variables as well as 30 day and 6 month outcomes were collected in 201 of these patients who were on coumadin. They were divided into 3 groups: [Group 1 INR <1.5 (85, 42.2%), Group 2 INR 1.5–1.9 (69, 34.3%) and Group 3 INR ≥2.0 (47, 23.2%)] to evaluate the impact of INR on complication rates. Results: The mean age was 68 ± 14.3 years. Atrial fibrillation was the main indication for anticoagulation (58%). Device procedures included pacemaker implantation (63.2%), pulse generator replacement or lead revision (19.4%), ICD implantation (13.4%) and ICD revision (4%). Submuscular pockets were used in 21% of patients while the cephalic vein was accessed in the majority (64%). Baseline demographic and procedural variables between the three groups were no different. Peri-procedural heparin use was similar in the three groups. At 30 day follow-up minor haematomas occurred in 1 (1.2%), 2 (3.0%) and 2 (4.3%) of groups 1–3 respectively (p = 0.53). None required treatment. One major haematoma requiring evacuation and one pocket infection requiring system removal occurred in group 2. Combined complication rates (haematoma and infection) at 6 months were no different between the 3 groups (p = 0.15). Conclusion: Coumadin is not associated with excess bleeding risks. doi:10.1016/j.hlc.2007.06.150