Given an abstract, indicate which of the provided candidate titles (Option1 and Option2) best describes it (respond with the text of the title, not option1/2).

[Q]: Abstract: Low-level activity at the end of the QRS complex was analyzed from 63 thoracic leads in 15 normal subjects and in 21 patients with ventricular tachycardia (VT). The latter had old myocardial infarction and no conduction disturbances and had not been receiving antiarrhythmic drugs. In both normal subjects and patients with VT, isopotential maps of the time-averaged and filtered (25 Hz high-pass) electrocardiograms during the terminal portion of the QRS were dipolar, i.e., they showed single positive and negative regions. For patients with VT, the extrema were either distant, with one over the precordial area and the other over the back, or close together in the precordial region. In 10 patients, maps recorded after administration of antiarrhythmic drugs remained the same while QRS duration was prolonged. In six patients, maps recorded before antiarrhythmic surgery showed distant extrema for septal or posterobasal VT sites of origin and close extrema for anterior or posteroapical sites. Generally, QRS duration was reduced and maps were modified after surgery. Late potentials can be well detected with only three orthogonal leads because their distributions are dipolar, but maps provide additional information about their distribution, which may be related to conduction delay sites and possibly to VT sites of origin. Sources near the torso surface would produce close extrema, whereas deeper sources would produce distant extrema.
Which is the apt title for the abstract? option1: Characterization of the spatial distribution of late ventricular potentials by body surface mapping in patients with ventricular tachycardia. option2: The strictures, sinuses, and fissures of Crohn's disease.
[A]: Characterization of the spatial distribution of late ventricular potentials by body surface mapping in patients with ventricular tachycardia.

[Q]: Abstract: It has been suggested that the risk of breast cancer is increased by oral contraceptive use before the first birth, or by use before age 25, particularly if certain formulations are used. These hypotheses were evaluated in a hospital-based case-control study. A total of 521 patients under age 45 with breast cancer were compared with 521 controls matched for age, time of interview, and geographic area. Oral contraceptive use before the first birth was reported by 155 patients and 137 controls. With allowance for confounding by multivariate analysis, the estimated relative risk was 1.0 (95% confidence interval, 0.6-1.5). The estimate was 1.0 (0.2-3.9) for any use among nulliparous women and 0.6 (0.3-1.3) for use before the first birth among parous women. Use before age 25 was reported by 145 patients and 141 controls, and the multivariate relative risk estimate was 1.0 (0.7-1.6); the results were similar when use of specific formulations was examined. For oral contraceptive use before either the first birth or age 25, the relative risk estimates were compatible with 1.0 for use of five or more years' duration or an interval since first use of at least 15 years. There was also no evidence of an increased risk in any subgroup including those at increased underlying risk because of factors such as a family history of breast cancer or a history of cystic breast disease. The findings suggest that, up to age 45, the risk of breast cancer is not influenced by the use of oral contraceptives before the first birth or before age 25 even if the use lasted for five or more years.
Which is the apt title for the abstract? option1: Breast cancer risk in relation to early oral contraceptive use. option2: Centrode patterns in the lumbar spine. Baseline studies in normal subjects.
[A]: Breast cancer risk in relation to early oral contraceptive use.

[Q]: Abstract: Pulmonary venous flow was evaluated by pulsed Doppler echocardiography in 38 patients with total anomalous pulmonary venous connection. Twenty-nine of these 38 had no associated intracardiac anomaly (Group I), and 9 had complex intracardiac anatomy associated with low pulmonary blood flow (Group II). In Group I the drainage was infracardiac in nine, supracardiac in seven, intracardiac in eight and mixed in five. In both groups, in those with venous obstruction the flow in the individual pulmonary veins and ascending or descending vein was nonphasic, varying only with respiration. Flow in the absence of obstruction was phasic, varying with the cardiac cycle. Distal to a site of obstruction the flow was nonlaminar and of high velocity irrespective of the amount of pulmonary blood flow. The pulsed Doppler technique provides important physiologic information in the patient with total anomalous pulmonary venous connection before surgical intervention.
Which is the apt title for the abstract? option1: Pulsed Doppler echocardiography in the preoperative evaluation of total anomalous pulmonary venous connection. option2: Hepatitis B vaccine [letter]
[A]:
Pulsed Doppler echocardiography in the preoperative evaluation of total anomalous pulmonary venous connection.