Intracardiac Thrombi in Preterm Infants-A Case Study and Review of the Literature.

Intracardiac thrombi in preterm infants are not common but may lead to fatal outcomes. Predisposing and risk factors include small vessel size, hemodynamic instability, immaturity of the fibrinolytic system, indwelling central catheters and sepsis. In this paper, we present our own experience with a case of a catheter-related right atrial thrombus in a preterm infant, which was successfully treated with an aspiration thrombectomy. Then, we review the literature on intracardiac thrombosis in preterm infants: epidemiology, pathophysiology, clinical signs, echocardiographic diagnostic features and treatment options are discussed.

[ALTERATIONS IN SENSITIVE MEASURES OF CARDIAC FUNCTION IN HEALTHY NEONATES DURING PHOTOTHERAPY].

OBJECTIVES: Phototherapy has been reported to reduce coronary blood flow in neonates but without affecting gross measures of cardiac function. The aim of our current study was to evaluate earlier, more sensitive changes in cardiac function during phototherapy. METHODS: Nineteen neonates with jaundice treated with phototherapy had Doppler echocardiographic evaluation, before, during and after phototherapy and were compared to 25 matched controls. Sensitive measures for cardiac performance in this study included left ventricular dimension, ventricular Doppler parameters and regional function assessment. RESULTS: Phototherapy was associated with a significant increase in heart rate. In addition, atrioventricular valve closure to opening interval decreased significantly during phototherapy while ventricular ejection times tended to decrease. However, left and right ventricular filling parameters and outflow velocity parameters, longitudinal tissue-Doppler annular velocities and myocardial performance indices were not affected by phototherapy and were similar to those in controls. Coronary blood velocities and integrals decreased significantly during phototherapy. CONCLUSIONS: Our study found no differences in early and sensitive measures of cardiac performance including the diastolic and systolic function, despite modestly lower flow in coronary arteries among healthy neonates during phototherapy.

The effect of patent ductus arteriosus on coronary artery blood flow in premature infants: a prospective observational pilot study.

OBJECTIVE: To compare coronary flows between premature infants with and without hemodynamically significant patent ductus arteriosus (hsPDA) and to determine if coronary flow is influenced by medical PDA treatment. DESIGN: Prospective, observational pilot study. Forty-three infants <32 weeks gestation underwent echocardiography when routinely indicated. Study group included infants with hsPDA requiring treatment. Comparison groups included infants with nonsignificant PDA and infants without PDA. RESULTS: The study group (n = 13), compared with the comparison groups with nonsignificant PDA (n = 12) and without PDA (n = 18) had higher troponin levels (p = 0.003 and 0.004, respectively). In infants with hsPDA compared with infants with no PDA there was a significant increase in myocardial oxygen demand and decrease in left main coronary artery flow, with nonsignificant increase in cardiac output. CONCLUSIONS: Decrease in coronary artery flows and higher troponin values may suggest a "steal effect," not allowing to meet the elevated myocardial oxygen demand in infants with hsPDA.

Long-term performance of bicuspid and quadricuspid aortic valves: Similarities and differences.

While bicuspid aortic valve (BAV) is a common congenital cardiac anomaly, quadricuspid aortic valve (QAV) is rare. The usual three-leaflet aortic valve is characterized by engineering advantages with superior long-term performance, and thus, degenerative changes and significant functional deterioration appear at advanced age. AIM: Evaluation of long-term performance, similarities, and differences between QAV and BAV. METHODS: Screening of 19 000 consecutive echocardiographic studies was performed. RESULTS: BAV was reported in 131 subjects with a prevalence of 0.7%, while QAV was seen in 11 with a prevalence of 0.06%, P < .00001. Age of BAV patients was younger, 45 ± 20 years vs 62 ± 17 years in QAV, P < .05, with higher proportion of females in those with QAV, 40% vs 30%. Chamber diameters were similar in both groups. Higher atrial contraction-A-wave mitral peak velocities and longer E-wave deceleration times were found in subjects with QAV, P < .05 for both. Dilated ascending aorta was found in 25% of patients with BAV and in 18% of those with QAV, P = .2. Moderate and severe aortic valve stenosis were found in 21% of patients with BAV and in 27% of those with QAV, P = ns. More than moderate aortic regurgitation was found in 15.5% of BAV patients and in 9% of QAV, P = ns. Aortic valve infective endocarditis was found in 1.5% of BAV patients and in 9% of those with QAV. CONCLUSIONS: BAV is a common congenital anomaly, while QAV is rare. Similar prevalence of significant valve disease and aortopathy was found in both anomalies, though at younger age in BAV patients.

Platelet counts on admission affect coronary flow, myocardial perfusion and left ventricular systolic function after primary percutaneous coronary intervention.

BACKGROUND: Patients with acute ST-elevation myocardial infarction (STEMI) and increased platelet count treated by fibrinolysis have worse outcomes. AIM: The aim of this study was to test the hypothesis that platelet blood count at admission in patients with acute STEMI treated by primary percutaneous coronary intervention affects coronary flow, myocardial perfusion and recovery of left ventricular systolic function. METHODS: A total of 174 patients presenting with acute anterior STEMI and treated with primary percutaneous coronary intervention were included and divided into subgroups of admission platelet blood count of <200 K, 200-300 K, 300-400 K and >400 K. Evaluation of coronary artery flow and myocardial blush grade was performed according to the TIMI criteria. Electrocardiographic ST elevation resolution post-primary percutaneous coronary intervention was evaluated. Doppler echocardiographic evaluation of left anterior descending coronary artery velocities early and late after primary percutaneous coronary intervention and assessment of left ventricular ejection fraction and wall motion score index (WMSI) of left ventricular and left anterior descending coronary artery territory were performed. RESULTS: Post-primary percutaneous coronary intervention TIMI, myocardial blush grade and ST elevation resolution were similar in all groups. Patients with platelet counts <200 K had higher peak diastolic left anterior descending coronary artery velocity both early and late after primary percutaneous coronary intervention, and higher prevalence of left anterior descending coronary artery velocity deceleration time exceeding 600 ms, (45.5% vs. 40%, P<0.05). Patients with platelet counts >400 K presented with worse left ventricular ejection fraction, left ventricular WMSI and left anterior descending coronary artery WMSI, and before discharge this subgroup had worse left ventricular WMSI and left anterior descending coronary artery WMSI, P<0.01. CONCLUSIONS: Patients with anterior STEMI treated by primary percutaneous coronary intervention with lower admission platelet count had higher left anterior descending coronary artery diastolic velocities, better myocardial perfusion with more patients having left anterior descending coronary artery-descending coronary artery velocity deceleration time >600 ms. Patients with higher platelet counts had lower left ventricular systolic function both at admission and before discharge.

Doppler echocardiographic myocardial stunning index predicts recovery of left ventricular systolic function after primary percutaneous coronary intervention.

BACKGROUND: Myocardial stunning is responsible for partially reversible left ventricular (LV) systolic dysfunction after successful primary percutaneous coronary intervention (PPCI) in patients with acute ST-elevation myocardial infarction (STEMI). AIM: To test the hypothesis that early coronary blood flow (CBF) to LV systolic function ratios, as an equivalent to LV stunning index (SI), predict recovery of LV systolic function after PPCI in patients with acute STEMI. METHODS: Twenty-four patients with acute anterior STEMI who had successful PPCI were evaluated and compared to 96 control subjects. Transthoracic echocardiography with measurement of LV ejection fraction (EF), LV, and left anterior descending (LAD) coronary artery area wall-motion score index (WMSI) as well as Doppler sampling of LAD blood velocities, early after PPCI and 5 days later, were performed. SI was evaluated as the early ratio of CBF parameters in the LAD to LV systolic function parameters. RESULTS: Early SI-LVEF well predicted late LVEF (r=.51, P<.01) and the change in LVEF (r=.48, P<.017). Early SI-LVMSI predicted well late LVEF (r=.56, P<.006) and the change in LVEF (r=.46, P<.028). Early SI-LADWMSI predicted late LVEF (r=.44, P<.028). Other SI indices measured as other LAD-CBF to LV systolic function parameters were not predictive of late LV systolic function. CONCLUSIONS: LV stunning indices measured as early LAD flow to LVEF, LVWMSI, and LADWMSI ratios well predicted late LVEF and the change in LVEF. Thus, greater early coronary artery flow to LV systolic function parameter ratios predict a better improvement in late LV systolic function after PPCI.

Effects of Phototherapy on Coronary Blood Flow in Healthy Neonates: A Pilot Study.

BACKGROUND: Phototherapy has been reported to alter blood flow to various tissues. We hypothesized that during phototherapy the coronary blood flow will decrease because of a 'steal effect' to the periphery. OBJECTIVES: To evaluate the effects of phototherapy on coronary blood flow in healthy, jaundiced, term neonates. METHODS: Flow velocity [peak diastolic velocity (Vd)] and flow measures [diastolic time velocity integral (TVId) and flow index (FI)] in the left main (LM) and left anterior descending (LAD) coronary arteries were prospectively studied with 2D/pulsed Doppler ultrasound before, during and after phototherapy in 19 healthy term, jaundiced neonates (study group) and in matched nonjaundiced controls (25 neonates). Significance was set at p < 0.05. RESULTS: The neonates' characteristics were comparable in both groups. Sequential studies in the study group showed no significant decrease in measures of velocity and flow during phototherapy; however, there was a significant increase in some of these measures (Vd and TVId in the LM coronary artery, and Vd in the LAD coronary artery) after phototherapy. Velocity (Vd) and flow measures (TVId and FI) in the LAD coronary artery, but not in the LM coronary artery, were significantly lower when comparing the study group during phototherapy with the controls. In a multivariate model, phototherapy was an independent variable affecting Vd and TVId in LAD coronary arteries. Measures of cardiac output did not change significantly throughout the study. CONCLUSIONS: While part of our findings may suggest a modestly lower flow in coronary arteries during phototherapy, we conclude that no clinically significant alteration in coronary arterial flow occurs during phototherapy in healthy term neonates.

Differences in coronary artery blood velocities in the setting of normal coronary angiography and normal stress echocardiography.

BACKGROUND: Normal left anterior descending (LAD) coronary artery as determined by coronary angiography is considered not only to reflect normal angiography but also to correlate with normal anatomy and function. However, subjects who undergo coronary angiography may differ from those who do not need to have invasive evaluation even if their functional noninvasive studies like dobutamine stress echocardiography (DSE) were normal. AIM: LAD velocities in subjects with normal angiography and those with normal DSE are equal. METHODS: A total of 244 subjects were evaluated, 78 had normal LAD by angiography and 166 had normal LAD by DSE. All had Doppler sampling of LAD velocities by transthoracic echocardiography. RESULTS: Velocity was higher in the angiographic subgroup in diastole 41 ± 23 vs 33 ± 14 cm/s, p = 0.0078; systole 18 ± 14 vs 13 ± 7 cm/s, p = 0.012; diastolic integral 12.6 ± 5 vs 9.8 ± 3.8 cm, p = 3.15 × 10(-5); systolic velocity integral 4 ± 2.9 vs 2.8 ± 1.9, p = 0.0014. While heart rate was similar in both groups, the product of diastolic velocity integral and heart rate of the LAD in the angiographic group was higher: 902 ± 450 vs 656 ± 394, p = 0.00599. Diastolic velocity deceleration time was similar in both groups. Coronary flow reserve defined as diastolic velocity ratio before and immediately after DSE correlated negatively with baseline velocity, r = -0.4. CONCLUSIONS: Mode of defining normality of coronary artery affects velocity behavior of the vessel, reflecting functional differences possibly related to microvasculature and vasodilatation.

Sequential evaluation of coronary flow patterns after primary angioplasty in acute anterior ST-elevation myocardial infarction predicts recovery of left ventricular systolic function.

BACKGROUND: Function of the microcirculation after primary percutaneous coronary intervention (PCI) is dynamic and contributes to unpredictability of recovery of left ventricular (LV) systolic function. AIM: This study was conducted to evaluate sequential Doppler velocity parameters of the left anterior descending coronary artery (LAD) in predicting recovery of global and regional LV systolic function. METHODS: Thirty-five consecutive patients, 24 males, age 59 ± 12 years, with acute anterior ST-elevation myocardial infarction (STEMI) who had primary PCI were studied. Thrombolysis in myocardial infarction (TIMI) and myocardial blush grades were evaluated. Transthoracic echocardiographic (TTE) studies, evaluation of left ventricular ejection fraction (LVEF), LAD territory wall-motion score index (WMSI), and sampling of LAD Doppler velocities up to 6 hours post-PCI, 48 hours postprocedure, and predischarge were performed. RESULTS: Thrombolysis in myocardial infarction grade before PCI averaged 0.86 ± 1.19 and post-PCI 2.89 ± 0.32, P < 0.05. Myocardial blush grade before PCI was 0.41 ± 0.98 and after PCI 2.22 ± 0.93, P < 0.05. Diastolic velocity deceleration time (DDT) in the LAD early after PCI was less than 600 ms in 16 subjects. Immediately after PCI, in subjects with DDT > 600 ms, LVEF was 38.5 ± 6% and predischarge 49.2 ± 8.7%, P = 9.77 × 10−5 and LAD-WMSI decreased from 2 ± 0.38 to 1.4 ± 0.48, P = 0.000163. In subjects with DDT < 600 ms LAD-WMSI did not change significantly. Early and minimal LAD-DDT correlated with improvement in LV systolic function, r = 0.6, whereas post-PCI blush grade had lower correlation with LVEF, r = 0.39. CONCLUSIONS: Global and regional LV systolic function after PCI in acute anterior MI can be predicted by LAD-DDT better than by post-PCI myocardial blush.

Left anterior descending coronary artery flow after primary angioplasty in acute anterior ST-elevation myocardial infarction: how much flow is needed for left ventricular functional recovery?

UNLABELLED: The treatment of choice in acute ST-elevation myocardial infarction (STEMI) is primary percutaneous coronary intervention (PPCI). Although, thrombolysis in myocardial infarction (TIMI) and myocardial blush grade (MBG) measures provide semi-quantitative flow evaluation after PPCI, serial and quantitative volumetric flow evaluation is still lacking. AIM: Serial assessment of left anterior descending (LAD) coronary artery flow in patients with anterior myocardial infarction (MI), immediately after PPCI, 48 h later and pre-discharge and compare findings in patients with optimal and suboptimal PPCI result and their relation to left ventricular ejection fraction (LVEF). METHODS: Velocities in the LAD were recorded within 6 h after PPCI and one week later in 36 patients presenting with acute anterior STEMI. Sixteen patients had TIMI and MBG less than 3 after PPCI were considered to have suboptimal result. Sampling of LAD coronary artery velocity was obtained from trans-thoracic Doppler. Flow in the LAD coronary artery was estimated using heart rates, Doppler time velocity integrals and LAD color Doppler diameters. RESULTS: Diastolic LAD coronary artery flow immediately after PPCI in subjects with suboptimal PPCI, 29 ± 21 ml/min was lower than in those with optimal result, 39.8 ± 21 ml/min, p<0.05. Diastolic flow in the LAD coronary artery increased to 50.3 ± 28.5 ml/min two days after PPCI in patients with suboptimal PPCI, p=0.04, and to 49.6 ± 13.8 ml/min in those optimal result, p=0.04. LVEF increased by 9% in patients with optimal PPCI, p=0.004, and did not change in the other group. CONCLUSIONS: (a) After PPCI, flow in the LAD coronary artery was dynamic; (b) in the presence of suboptimal PPCI, early LAD coronary artery flow was reduced; (c) pre-discharge, LAD coronary artery flow increased; and (d) LVEF increased only in optimal PPCI group associated with higher early LAD coronary artery flow.

Effects of Left Ventricular Wall Motion Abnormality on Global and Regional Diastolic Function of the Left and Right Ventricles at Rest and After Stress.

BACKGROUND: Diastolic dysfunction precedes systolic dysfunction in patients with coronary artery disease. The aim of the study was to evaluate the effects of left ventricular (LV) wall motion abnormality (WMA) on diastolic LV and right ventricular (RV) function at rest and after stress. METHODS: Fifty-nine subjects, 15 with LV-WMA (abnormal group) and 44 without (normal group), underwent dobutamine stress echocardiography (DSE) studies, in addition to evaluation of LV and RV diastolic function before and after DSE. RESULTS: Resting mitral flow parameters were similar. DSE increased peak A-wave velocities in both groups, and mitral color slope only in normal subjects. After DSE, E-wave peak velocities and mitral color slope were higher in normal subjects, P < 0.05. At rest and after DSE systolic and diastolic pulmonary vein velocities were similar in both groups; however, DSE increased these velocities only in normal subjects, P < 0.05. Regional E-wave peak velocities of LV were higher at rest in normal subjects, P < 0.05. Both LV and RV, regional peak E-wave velocities were not affected by DSE. After DSE, regional A-wave peak velocities increased in all (P < 0.01), except at the lateral region (P = 0.07). DSE increased trans-tricuspid velocities in both groups, P < 0.05. Resting A-wave velocities were higher in normal subjects, P < 0.01. CONCLUSIONS: Global LV early diastolic filling parameters were not affected by LV-WMA at rest. LV-WMA blunted the response after stress. RV E-wave velocities increased after DSE, and were not affected by LV-WMA. LV-WMA reduced regional LV-E' velocities at rest but not the reserve. A-wave velocities were not affected by WMA and increased after DSE.

The Link between Right and Left Ventricular Systolic Performance at Rest and after Stress: Insights Into the Mechanism.

BACKGROUND: Right ventricular (RV) systolic performance is more difficult for evaluation compared to the left ventricle (LV). Despite differences in structure, RV myocardial fibers are in continuity with those of LV. The aim is assessment of the effects of LV wall motion abnormalities (WMA) on RV systolic function at rest and after stress. METHODS: Fifty nine subjects, 15 with LV-WMA underwent dobuatmine stress echocardiography (DSE) studies using the usual protocol. Measurement of tricuspid annular plane systolic excursion (TAPSE), velocity (TASV), mitral annular plane systolic excursion (MAPSE) and velocity (MASV), were performed before and immediately after DSE studies. RESULTS: TAPSE was lower, in those with LV-WMA than in those without, both at rest 20.5 ± 4.8 mm versus 24.9 ± 4.7 mm, P = 0.015 and after DSE studies, 21.5 ± 5.6 mm versus 27.65 ± 5.7 mm, P = 0.005. DSE studies did not change TAPSE significantly in the presence of LV-WMA. TASV at rest in those with LV-WMA was 16.5 ± 2.7 cm/sec and similar to that in those without, 17.6 ± 3 cm/sec. In both groups the velocity increased after DSE studies, 23.25 ± 7.5 cm/sec, P = 0.01 with LV-WMA, and 27.5 ± 6 cm/sec, P = 0.0005, without LV-WMA. Despite similar TASV at rest, the TAPSE/TASV ratio, indicating duration of shortening, was lower (124 ± 21 msec) in subjects with of LV-WMA, than in those without (145 ± 27 msec), P = 0.0065, implying increased after load for RV longitudinal shortening in the presence of LV-WMA. CONCLUSIONS: TAPSE is lower at rest and after DSE studies in subjects with LV-WMA than in subjects without; however, DSE studies increase TPASE only in the absence of LV-WMA. TASV increases after DSE studies and is similar at rest in both groups with or without LV-WMA. It seems that LV-WMA increases after load to RV longitudinal motion.

Palpography detects mechanical dyssynchrony and worsens with right ventricular pacing and reduced left ventricular ejection fraction.

BACKGROUND: QRS width and echocardiography-derived indices are limited predictors of response to resynchronization therapy. We applied digital palpography, using vibration resonance imaging, to investigate the effects of right ventricular pacing and left ventricular ejection fraction (LVEF) on mechanical and electrical dyssynchrony. METHODS: Forty-nine subjects were examined: 24 normal controls, 18 subjects with right ventricular apical pacing (12 with reduced LVEF), and seven subjects with reduced LVEF and narrow QRS. Digital measurement of QRS width was performed. Electric dyssynchrony index (EDI) was measured as the time interval between peak R-waves of the same QRS complex of simultaneously recorded standard limb electrocardiograms, L1 and L2. A matrix of 6 × 6 vibration recording transducers was applied to chest. The interval between the onset of Q-wave and the peak of amplitude vibration for each transducer was measured, and a three-dimensional map for the whole matrix of transducers was generated. Median values (QE1) were measured. Mechanical vibration systolic dyssynchrony index (VSDI) for each subject was determined as the standard deviation of the difference between the median value and each transducer interval. RESULTS: EDI was larger in subjects with right ventricular pacing. Mechanical dyssynchrony indices were larger with pacing and reduced LVEF. EDI correlated with QRS width (r(2) = 0.7), with VSDI (r(2) = 0.42), and with QE1 (r(2) = 0.74). QRS width correlated with QE1 (r(2) = 0.75). CONCLUSIONS: Digital chest palpography can determine dyssynchrony indices that are larger in subjects with right ventricular pacing and reduced LVEF and correlate with parameters of electrical dyssynchrony.

Application of Mitral Annular Systolic Displacements and Velocities for the Evaluation of Left Ventricular Systolic Function and Reserve.

BACKGROUND: Mitral annular systolic displacement from M-mode echocardiography and velocity from tissue Doppler imaging reflect subendocardial longitudinal systolic LV performance and may precede radial abnormalities. The aim of this study is to evaluate the utility of mitral annular systolic displacement (D) and velocity (V) during dobutamine stress echocardiography (DSE) in detecting left ventricular (LV) functional reserve and wall motion abnormality (WMA). METHODS AND RESULTS: Fifty-nine subjects, 15 with resting WMA, underwent DSE and measurement of mitral systolic (D) and (V) before and immediately after DSE. Annular septal (D) was lower in those with WMA than in those without, at rest 10.5 ± 4 cm versus 13.2 ± 2 cm, p = 0.015, and after DSE, 11.7 ± 3.8 cm versus 14 ± 2.25 cm, p = 0.036, but without significant change after stress. Annular systolic (V) at rest with WMA was 9.7 ± 1.8 cm/sec and similar to those without, 11.25 ± 2.7 cm/sec. In both groups the velocity increased after DSE, 14.5 ± 4.5 cm/sec, p = 0.025 with WMA and 17.8 ± 3.2 cm/sec, p = 1.99 x 10-10 in those without WMA. Velocities after DSE were lower in those with WMA, p = 2.25 x 10-6. CONCLUSIONS: To evaluate LV systolic performance mitral annular systolic longitudinal displacement is valuable at rest, but for assessment of LV functional reserve after stress velocities are better.