Gau, Gerald T.

Background: We conducted this study to assess the safety of symptom-limited cardiopulmonary exercise testing (CPX) in patients with varying severity of aortic stenosis (AS). We hypothesized that exercise testing would be safe, as defined by a rates for all-cause death of <0.01% and rate of nonfatal major cardiovascular (CV) events <0.1% within 24 hours of CPX. Secondary purpose of this study was to determine the frequency of complications during CPX. Methods: This cohort study was carried out with 308 consecutive patients with varying degree of AS (as determined by standard echocardiographic criteria) with no or equivocal symptoms who were referred for clinically indicated cardiopulmonary testing between 1994 and 2009. We did not include patients with pending or completed heart transplant, or ventricular assist device implantation. These patients underwent standard symptom limited CPX, and continuous monitoring of heart rate, blood pressure, and electrocardiogram was performed. Complications recorded included death, non-fatal major CV events (cardiac arrest, symptomatic and sustained ventricular or atrial tachycardia, and syncope), and minor events such as hypotension, non-sustained atrial and ventricular arrhythmias, positive exercise ECG and anginal pain. Results: The mean age of patients was 66 ± 14 years, and 252 (82%) were males. The number of patients with mild, moderate and severe AS were 44 (14%), 138 (49%), and 126 (41%) respectively. No death or major CV event occurred during or within 24 hours of CPX. Eleven patients developed supraventricular arrhythmias without compromising hemodynamic status, and one had asymptomatic non-sustained ventricular tachycardia. Detailed description of complications is presented in the Table 1 . Conclusion: Our results show that symptom-limited CPX is safe among AS patients with no or equivocal symptoms based on no deaths or major CV events in our cohort. Minor complications occurred in 110 patients (36%). Table 1 Mild AS (n=44) Moderate AS (n=138) Severe AS (n=126) Age 61.7 ± 15.3 66.5 ± 13.86 67.89 ± 12.74 Males 36 (81%) 128 (83%) 96 (85%) Test protocol O2 protocol 39 (86%) 123 (89%) 104 (82%) Other 5 15 22 Reason for termination Symptom-limited 41 (93%) 114 (82%) 96 (76%) Other 3 24 30 Chest pain None 41 (93%) 122 (88%) 117 (93%) Non-cardiac 0 2 0 Non-anginal 0 2 0 Anginal 2 14 9 Treadmill ECG interpretation Negative 27 (61%) 67 (49%) 45 (37%) Non-diagnostic 14 48 58 Positive 3 23 23 Ventricular arrhythmia None 42 (95%) 134 (97%) 122 (97%) 3-5 beats VT 2 3 4 NSVT 0 1 0 Supraventricular arrhythmia None 42 (95%) 135 (97%) 120 (95%) SVT ≤ 30 sec 2 3 4 SVT > 30 sec 0 0 1 Afib 0 0 1 BP response Normal 41 (93%) 117 (85%) 93 (74%) Hypotensive 3 21 33 AS = Aortic Stenosis, ECG = Electrocardiogram, VT = Ventricular tachycardia, NSVT = Non-sustained ventricular tachycardia, SVT = Supraventricular tachycardia, Afib = Atrial fibrillation, BP = Blood pressure

The use of roentgen videometry as a means of studying regional left ventricular wall dynamics and performance was evaluated in 32 patients undergoing coronary arteriography. Nine patients had normal coronary arteriograms and hemodynamic findings (group 1), 8 patients had generalized decrease in left ventricular contraction and abnormal hemodynamic findings (group 2), and 15 patients with coronary artery disease had regional wall dynamics abnormalities (group 3). Sixty-per-second determinations of wall thickness were performed in selected sites of the left ventricle. Measurements performed included end-diastolic wall thickness (EDTw), mean and peak rates of systolic wall thickening (m and p dTw/dt), and fractional systolic increase in wall thickness (ΔTw/EDTw). In patients with uniformly performing ventricles (groups 1 and 2), these parameters correlated well with other parameters of ventricular function. Best distinction between the "normal" group (group 1) and the "abnormal" group (group 2) was achieved when the rates of thickening (m and p dTw/dt) were utilized ( P < 0.001). In patients of group 3, three types of abnormal regional wall dynamics could be determined and quantified objectively: hypokinesia (decreased p dTw/dt), akinesia (p dTw/dt = 0), and dyskinesia (p dTw/dt < 0). The severity of the abnormality of the wall dynamics correlated well with the presence or absence of a previous infarction on the electrocardiogram, and the anatomic location was strongly correlated with the distribution and severity of coronary artery lesions within a given ventricle.

The echocardiographic features of Ebstein's anomaly include a large anterior chamber, paradoxic ventricular septal motion (type B), increased velocity and amplitude of anterior tricuspid leaflet (ATL) motion, and delayed closure of the ATL. This delayed closure has been thought to be secondary to right bundle-branch block (RBBB). We have studied two patients by simultaneous echocardiography and phonocardiography. The findings in both patients were similar. One patient had RBBB and therefore resembles the previously reported patients. However, the other patient had W-P-W preexcitation syndrome, type B, and is reported here in more detail. The ATL closure of this patient was markedly delayed in spite of right ventricular preexcitation. This finding gives further insight into the altered pathophysiology in Ebstein's anomaly and implies that the delayed ATL closure is probably not due to RBBB and may be a specific feature of this anomaly.

The effect of oral aspirin in doses known to influence in vitro platelet aggregation was evaluated in patients undergoing brachial artery catheterization. Neither arterial thrombus formation nor pulse reduction was affected in patients given aspirin when compared to controls. Aspirin in small doses does not decrease the incidence of vascular occlusion after brachial artery catheterization.

Echocardiograms were performed on 20 children who were 1-14 years old. Ten children had secundum atrial septal defects (ASD 2°); four had partial and two had complete atrioventricular canal defects (AVC); and three had partial and one had total anomalous pulmonary venous connection (APVC). Twenty-eight normal children were also examined. Echocardiograms of nine patients with ASD 2° revealed increased right ventricular dimension index (RVDI) and abnormal (paradoxic) ventricular septal (VS) motion. The remaining patient with ASD 2°, who had a Qp/Qs of 1.2 (smallest in the series), had a normal echocardiogram. All four patients with APVC had increased RVDI, and three had abnormal VS motion. The patient with normal septal motion had associated mild aortic stenosis, but he too had a small left-to-right shunt (19%). The echocardiograms of two patients with partial AVC revealed features similar to ASD 2°, but in the third patient who had significant mitral regurgitation (MR) the VS motion was normal, indicating that the degree of associated MR influences the VS motion in this anomaly. The septal motion was normal in both patients with complete AVC. Three patients in the series had abnormal systolic anterior motion of mitral valve. Postoperative echocardiograms revealed persistence of increased RVDI and "paradoxic" VS motion.