Browsing by keyword "Echocardiography, Doppler"

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    • Cardiac systolic and diastolic function at rest and exercise in subclinical hypothyroidism: effect of thyroid hormone therapy
      Arem, R.; Rokey, R.; Kiefe, Catarina I.; Escalante, D. A.; Rodriguez, A. (1996-10-01)
      Cardiac atrial and ventricular parameters were determined by Doppler two-dimensional echocardiography at rest and exercise in 8 patients with subclinical hypothyroidism (SCH) (6 women and 2 men; age range: 28-48 years) before and 3 months after achievement of a euthyroid state with incremental adjustment of L-thyroxine therapy. None of the patients had known heart disease. At 3 months of L-thyroxine therapy, TSH levels decreased from 14.8 +/- 9.4 mIU/L to 3.0 +/- 1.5 mIU/L and FTI increased from 7.1 +/- 1.8 to 8.1 +/- 1.9. The cardiac studies were performed at rest, and during incremental exercise load (50, 100, 150 W workload) on a Quinton exercise bicycle. No significant differences were found between the subclinical hypothyroid and euthyroid states in systolic blood pressure at rest (104.8 +/- 12.3 vs 105 +/- 10.1 mm Hg) and exercise (158 +/- 24.9 vs 158.5 +/- 20.9 mm Hg) or diastolic blood pressure at rest (70 +/- 4.7 vs 69 +/- 5.7 mm Hg) and exercise (86 +/- 11.4 vs 89.2 +/- 7.3 mm Hg). All echocardiographic atrial and ventricular parameters were similar before and during L-thyroxine therapy with the exception of a small but significant change in left ventricular diastolic dimension (4.5 +/- 0.3 vs 4.8 +/- 0.4 cm; p < 0.05). All Doppler parameters were not significantly affected by L-thyroxine therapy with the exception of preejection period at stage III exercise (51 +/- 17 vs 39 +/- 13 msec; p < 0.05). Preejection period at other stages of exercise showed trends toward similar differences between subclinical hypothyroidism and euthyroidism, but the differences were not statistically significant. We conclude that the cardiac structure and function overall remains for practical purposes normal in subclinical hypothyroidism. However, the latter may be responsible for a mild prolongation of the preejection period during exercise and a slightly smaller left ventricular diastolic dimension at rest, changes that may not be of clinical significance in patients without underlying heart disease.

    • Extent and severity of coronary artery disease by coronary CT angiography is associated with elevated left ventricular diastolic pressures and worsening diastolic function
      Lin, Fay Y.; Zemedkun, Micheas; Dunning, Allison; Gomez, Millie; Labounty, Troy M.; Asim, Muhammad; Horn, Evelyn; Aurigemma, Gerard P.; Maurer, Matthew S.; Roman, Mary; et al. (2013-09-01)
      BACKGROUND: Patients with flow-limiting coronary stenoses exhibit elevated left ventricular end-diastolic pressure (LVEDP) and abnormal left ventricular (LV) relaxation. OBJECTIVE: We investigated the relationship of extent and severity of coronary artery disease (CAD) by coronary CT angiography (CTA) to LVEDP and measures of LV diastolic dysfunction. METHODS: We identified consecutive patients undergoing coronary CTA and transthoracic echocardiography who were assessed for diastolic function. CAD was evaluated on a per-patient, per-vessel, and per-segment basis for intraluminal diameter stenosis by using an 18-segment model (0 = none, 1 = 1%-49%, 2 = 50%-69%, and 3 = 70%-100%) and summed over segments to obtain overall coronary plaque burden (segment stenosis score [SSS]; maximum = 54). Transthoracic echocardiography evaluated mitral inflow E wave-to-A wave ratio, tissue Doppler early mitral annual tissue velocity axial excursion, stage of diastolic dysfunction, and LV dimensions and estimated LVEDP from the ratio of mitral inflow velocity to early mitral annular (medial) tissue velocity. RESULTS: Four hundred seventy-eight patients (57% women; mean age, 57.9 +/- 14.6 years; 24.9% prior CAD) comprised the study population. Increasing per-patient maximal coronary stenosis, number of vessels with obstructive stenosis, and SSS were associated with increased LVEDP. The prevalence of advanced diastolic dysfunction increased with greater number of obstructive vessels. In multivariable analyses, SSS was associated with increased LVEDP (0.8 mm Hg per tertile increase in SSS, 0.5-1.1; P < .001); reduced E' axial excursion (-0.3; 95% confidence interval [CI], -0.5 to -0.1; P = .001), increased LV mass index (1.6 g/m(2) per tertile increase in SSS; P = .04), and increased relative wall thickness (0.005; 95% CI, 0.004-0.009; P = .03), with consistent relationships persisting even among persons with per-patient maximal stenosis < 50% and LV ejection fraction >>= 55%. CONCLUSIONS: Extent and severity of obstructive as well as nonobstructive CAD by coronary CTA are associated with increased LVEDP and measures of diastolic dysfunction. Elsevier Inc. All rights reserved.