Cardiac Responses to Prenatal Resistance Exercise with and without the Valsalva Maneuver

PURPOSE

Exercise guidelines recommend incorporating resistance exercise (RE) into a regular aerobic training program during pregnancy. However, few women do so because of uncertainties about the safety of prenatal RE, particularly regarding the Valsalva maneuver (VM). The aim of this study was to determine the acute cardiovascular responses to prenatal RE at different intensities, with and without VM.

METHODS

Healthy pregnant (n = 15; 22.9 ± 5.9 wk of gestation) and nonpregnant women (n = 15) were recruited. Maximal strength over 10 repetitions (10RM) for semireclined leg press was determined. Women underwent standardized assessments of cardiac structure, function and mechanics (echocardiography), heart rate (ECG), and blood pressure (photoplethysmography) at baseline, during RE at 20%, 40%, and 60% 10RM while free-breathing, and at 40% 10RM with VM. Significant differences were identified between subjects at baseline (independent t-tests), between and within subjects during free-breathing RE (general linear model, baseline as a covariate), and between and within subjects for 40% 10RM free-breathing versus VM (mixed-effects model).

RESULTS

Resting cardiac output, heart rate, and stroke volume were greater in pregnant women, without differences in blood pressure, ejection fraction, or cardiac mechanics. During free-breathing RE, pregnant women had a greater ejection fraction compared with nonpregnant women; however, all other hemodynamic variables were not different between groups. Cardiac mechanics during free-breathing RE across all intensities were not different between groups, with the exception that pregnant women had a lower apical circumferential strain that did not affect global cardiac function. No differences were observed between groups during 40% 10RM RE with and without VM.

CONCLUSIONS

Pregnant women have proportionate cardiac responses to light-moderate RE, both with and without the VM. These findings reinforce the safety of RE in healthy pregnancy.

Diabetes mellitus deteriorates left ventricular deformation in acromegaly-analysis from the three-dimensional speckle-tracking echocardiographic MAGYAR-Path study

Acromegaly and diabetes mellitus (DM) separately are associated with cardiovascular alterations and modified left ventricular (LV) deformation, which can be quantitatively assessed by three-dimensional speckle-tracking echocardiography (3DSTE). The present study aimed to assess the relationship between LV deformation and twist in the presence of DM in acromegaly. Thirty-seven acromegaly patients were involved in the study, but due to insufficient image quality 13 have to be excluded from analysis. Therefore, the present study comprised 24 acromegaly patients, from which 5 had DM. Their data was compared to 35 age- and gender matched healthy controls. Complete two-dimensional Doppler echocardiography extended with 3DSTE were performed in all patients and controls. Only non-diabetic acromegaly cases had increased global and mean segmental LV radial strain, diabetic acromegaly patients had similar LV radial strain as compared to that of healthy subjects. Other LV strain parameters did not show any difference between diabetic and non-diabetic acromegaly patients. While LV basal rotation was similar among the groups, LV apical rotation was reduced in both diabetic and non-diabetic patients as compared to healthy subjects. However, diabetic acromegaly patients had tendentiously higher values. The ratio of absence of LV twist called as LV rigid body rotation was similar between the groups examined. Diabetes mellitus deteriorates left ventricular deformation in acromegaly.

Use of spectral tracking technique to evaluate the changes in left ventricular function in patients undergoing chemotherapy for colorectal cancer

To evaluate the changes in left ventricular myocardial function in patients with colorectal cancer undergoing chemotherapy with mFOLFOX6 (oxaliplatin + 5-fluorouracil + calcium folinate) using three-dimensional speckle-tracking echocardiography (3D-STE). Data were collected from 30 patients diagnosed with colorectal cancer in our hospital treated with mFOLFOX6. We used 3D-STE to measure the following parameters of left ventricle function: global longitudinal strain (GLS), global area strain (GAS), global circumferential strain (GCS), global radial strain (GRS), and left ventricular twist (LVtw). Myocardial composite index (MCI) was calculated from measured values (MCI = GLS × LVtw). The above listed parameters were compared before and after chemotherapy. Receiver operating curves (ROC) were prepared for each parameter and analyzed to identify correlations among MCI, LVEF, GLS, and cTnT. Compared with the pre-chemotherapy state, the absolute values of MCI, LVtw, GLS, GAS, GCS, and GRS decreased with increasing cumulative doses of chemotherapeutic drugs. The absolute values of GAS, GLS, MCI, and LVtw decreased after the first cycle of chemotherapy (P < 0.05). The areas under the ROC curves for MCI and GLS were 0.903 and 0.838, respectively. The correlation observed between MCI and cTnT (r = - 0.7228) was found to be stronger than that between GLS and cTnT (r = - 0.6008). In conclusion, 3D-STE may help detect early changes in left ventricular myocardial function caused by mFOLFOX6 treatment in patients with colorectal cancer. MCI is a relatively sensitive index among the various measurable parameters.

Abnormal left ventricular global strain during exercise-test in young healthy smokers

Background. It is unknown how much precociously the cigarette smoking (CS) may compromise the integrity of the cardiovascular (CV) system. Myocardial function can be routinely assessed by conventional echocardiography, but abnormalities are only detected when somewhat a remodelling has already occurred. These limitations could be overcome by strain imaging. Methods. We evaluated whether young smokers with normal left ventricular (LV) geometry, wall motion and ejection fraction may present abnormalities in myocardial deformation, both at rest and during physical effort. We selected 50 young smokers with no additional CV risk factors, and 60 non-smokers to undergo a standardized exercise-test. Consistently, we evaluated the CV adaptation to exercise by both conventional echocardiography and speckle-tracking analysis (2D-STE). Results. We found no difference between smokers and controls regarding baseline characteristics; as expected, smokers presented with lower HDL-cholesterol (p < 0.005), and higher fibrinogen, C-reactive protein (CRP), and interleukin-6 (p < 0.001). Conventional echocardiography parameters were not different between groups, while we detected a different behaviour of global longitudinal strain (GLS), global circumferential strain (GCS) and twist by 2D-STE during exercise-test. Indeed, GLS, GCS and twist behaved differently during exercise test in smokers with respect to controls. We found an association between CS, inflammation and LV mechanics changes uncovered by physical effort, and regression analysis confirmed that the intensity of the exposure to cigarette smoking, together with the inflammatory status (CRP, fibrinogen and Il-6) plasma levels, drive this impairment. Conclusions. We confirm strain imaging (2D-STE) as a very useful tool to identify early changes in cardiac mechanics, as adaptation to exercise; our findings may reflect a very precocious functional abnormality in active smokers, likely long before structural damage occurs.

Left ventricular synchrony, torsion, and recoil mechanics in Ebstein's anomaly: insights from cardiovascular magnetic resonance

BACKGROUND

Disease progression and heart failure development in Ebstein's Anomaly (EA) of the tricuspid valve is characterized by both right and left ventricular (LV) deterioration. The mechanisms underlying LV dysfunction and their role in heart failure development are incompletely understood. We hypothesized that LV dyssynchrony and impaired torsion and recoil mechanics induced by paradoxical movement of the basal septum may play a role in heart failure development.

METHODS

31 EA patients and 31 matched controls underwent prospective cardiovascular magnetic resonance (CMR). CMR feature tracking (CMR-FT) was performed on apical, midventricular and basal short-axis and 4D-volume analysis was performed using three long-axis views and a short axis cine stack employing dedicated software. Circumferential uniformity ratio estimates (CURE) time-to-peak-based circumferential systolic dyssynchrony index (C-SDI), 4D volume analysis derived SDI (4D-SDI), torsion (Tor) and systolic (sysTR) and diastolic torsion rate (diasTR) were calculated for the LV. QRS duration, brain natriuretic peptide, NYHA and Total R/L-Volume Index (R/L Index) were obtained.

RESULTS

EA patients (31.5 years; controls 31.4 years) had significantly longer QRS duration (123.35 ms ± 26.36 vs. 97.33 ms ± 11.89 p < 0.01) and showed more LV dyssynchrony (4D-SDI 7.60% ± 4.58 vs. 2.54% ± 0.62, p < 0.001; CURE 0.77 ± 0.05 vs. 0.86 ± 0.03, p < 0.001; C-SDI 7.70 ± 3.38 vs. 3.80 ± 0.91, p = 0.001). There were significant associations of LV dyssynchrony with heart failure parameters and QRS duration. Although torsion and recoil mechanics did not differ significantly (p > 0.05) there was an association of torsion and recoil mechanics with dyssynchrony parameters CURE (sysTR r = -0.426; p = 0.017, diasTR r = 0.419; p = 0.019), 4D-SDI (sysTR r = 0.383; p = 0.044) and C-SDI (diasTR r = -0.364; p = 0.044).

CONCLUSIONS

EA is characterized by LV intra-ventricular dyssynchrony, which is associated with heart failure and disease severity parameters. Markers of dyssynchrony can easily be quantified from CMR-FT, and may have a role in the assessment of altered cardiac function, carrying potential management implications for EA patients.