Patients with Fontan circulation have abnormal aortic wave propagation patterns: A wave intensity analysis study

Wave intensity analysis (WIA) has found particular applicability in the coronary circulation where it can quantify traveling waves that accelerate and decelerate blood flow. The most important wave for the regulation of flow is the backward-traveling decompression wave (BDW). Coronary WIA has hitherto always been calculated from invasive measures of pressure and flow. However, recently it has become feasible to obtain estimates of these waveforms noninvasively. In this study we set out to assess the agreement between invasive and noninvasive coronary WIA at rest and measure the effect of exercise. Twenty-two patients (mean age 60) with unobstructed coronaries underwent invasive WIA in the left anterior descending artery (LAD). Immediately afterwards, noninvasive LAD flow and pressure were recorded and WIA calculated from pulsed-wave Doppler coronary flow velocity and central blood pressure waveforms measured using a cuff-based technique. Nine of these patients underwent noninvasive coronary WIA assessment during exercise. A pattern of six waves were observed in both modalities. The BDW was similar between invasive and noninvasive measures [peak: 14.9 ± 7.8 vs. −13.8 ± 7.1 × 104 W·m−2·s−2, concordance correlation coefficient (CCC): 0.73, P < 0.01; cumulative: −64.4 ± 32.8 vs. −59.4 ± 34.2 × 102 W·m−2·s−1, CCC: 0.66, P < 0.01], but smaller waves were underestimated noninvasively. Increased left ventricular mass correlated with a decreased noninvasive BDW fraction ( r = −0.48, P = 0.02). Exercise increased the BDW: at maximum exercise peak BDW was −47.0 ± 29.5 × 104 W·m−2·s−2 ( P < 0.01 vs. rest) and cumulative BDW −19.2 ± 12.6 × 103 W·m−2·s−1 ( P < 0.01 vs. rest). The BDW can be measured noninvasively with acceptable reliably potentially simplifying assessments and increasing the applicability of coronary WIA.

Download Full-text

Differential Effect of Atrial Pacing on Left Ventricular-Derived Compression and Decompression Waves in Ascending Aorta of Adult Sheep: Wave Intensity Analysis

Heart Lung and Circulation ◽

10.1016/j.hlc.2012.05.038 ◽

2012 ◽

Vol 21 ◽

pp. S12-S13

Author(s):

J. Smolich ◽

M. Cheung ◽

D. Penny

Keyword(s):

Differential Effect ◽

Left Ventricular ◽

Ascending Aorta ◽

Wave Intensity ◽

Atrial Pacing ◽

Intensity Analysis ◽

Wave Intensity Analysis ◽

Adult Sheep

Download Full-text

Wave intensity analysis of carotid artery: A noninvasive technique for assessing hemodynamic changes of hyperthyroid patients

Journal of Huazhong University of Science and Technology [Medical Sciences] ◽

10.1007/s11596-010-0563-9 ◽

2010 ◽

Vol 30 (5) ◽

pp. 672-677 ◽

Cited By ~ 4

Author(s):

Yanrong Zhang ◽

Manwei Liu ◽

Meiling Wang ◽

Li Zhang ◽

Qing Lv ◽

...

Keyword(s):

Carotid Artery ◽

Wave Intensity ◽

Intensity Analysis ◽

Wave Intensity Analysis ◽

Hemodynamic Changes ◽

Noninvasive Technique ◽

Hyperthyroid Patients

Download Full-text

Wave intensity analysis of left atrial mechanics and energetics in anesthetized dogs

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00837.2006 ◽

2007 ◽

Vol 292 (3) ◽

pp. H1533-H1540 ◽

Cited By ~ 8

Author(s):

Tracy N. Hobson ◽

Jacqueline A. Flewitt ◽

Israel Belenkie ◽

John V. Tyberg

Keyword(s):

Mitral Valve ◽

Pulmonary Veins ◽

Left Ventricular ◽

Wave Intensity ◽

Intensity Analysis ◽

Wave Intensity Analysis ◽

Volume Loading ◽

Forward Movement ◽

Reflected Wave ◽

Left Atrial Mechanics

The left atrium (LA) acts as a booster pump during late diastole, generating the Doppler transmitral A wave and contributing incrementally to left ventricular (LV) filling. However, after volume loading and in certain disease states, LA contraction fills the LV less effectively, and retrograde flow (i.e., the Doppler Ar wave) into the pulmonary veins increases. The purpose of this study was to provide an energetic analysis of LA contraction to clarify the mechanisms responsible for changes in forward and backward flow. Wave intensity analysis was performed at the mitral valve and a pulmonary vein orifice. As operative LV stiffness increased with progressive volume loading, the reflection coefficient (i.e., energy of reflected wave/energy of incident wave) also increased. This reflected wave decelerated the forward movement of blood through the mitral valve and was transmitted through the LA, accelerating retrograde blood flow in the pulmonary veins. Although total LA work increased with volume loading, the forward hydraulic work decreased and backward hydraulic work increased. Thus wave reflection due to increased LV stiffness accounts for the decrease in the A wave and the increase in the Ar wave measured by Doppler.

Download Full-text