[Sleep-disordered breathing in patients with difficult-to-control hypertension]. / Trastornos respiratorios durante el sueño en pacientes con hipertensión arterial de difícil control.

OBJECTIVE: To analyze the relationship between sleep-disordered breathing and difficult-to-control arterial hyper-tension. PATIENTS AND METHODS: Patients were considered to have difficult-to-control hypertension when mean systolic blood pressure was 125 mm Hg or higher and/or mean diastolic blood pressure was more than or equal to 80 mm Hg (as recorded during 2 24-hour ambulatory monitoring studies) despite the use of 3 or more antihypertensive drugs. Respiratory polygraphy using the AutoSet device (ResMed Corp, Sydney, Australia) was then performed to study sleep-disordered breathing in all patients. RESULTS: Forty-nine patients with a mean (SD) age of 68.1 (9.1) years, mean systolic and diastolic pressures of 152.5 (13)/89.2 (8.5) mm Hg, and an average of 3.5 prescribed drugs were included in the study. The mean apnea-hypopnea index (AHI) was 26.2 (19.5) and events were predominantly obstructive. Patients with severe sleep apnea-hypopnea syndrome (SAHS) (AHI > or = 30; 40.8%) showed more uncontrolled daytime (P = .017) and nighttime (P = .033) systolic pressure than the rest, as well as higher daytime diastolic pressure (P = .035) and a greater consumption of drugs than those without severe SAHS (AHI < 10; 28.6%) (P = .041). The study population as a whole showed a significant correlation between blood pressure and obesity. There was a significant correlation (adjusted for age and sex) with AHI only in patients with SAHS. AHI was found to be the independent predictor with the greatest effect on blood pressure in these patients. CONCLUSIONS: Prevalence of SAHS was very high in patients with difficult-to-control hypertension. In patients with SAHS, AHI was found to be the independent predictor with the greatest affect on arterial blood pressure.

Low-dose dobutamine testing using contrast left ventriculography in the same session as coronary angiography predicts the improvement of left ventricular function after coronary angioplasty in postinfarction patients.

The role of percutaneous transluminal coronary angioplasty (PTCA) in the subacute or chronic phases of myocardial infarction remains controversial. This study investigates the usefulness of dobutamine contrast left ventriculography in a single session with coronary angiography for predicting the improvement of ventricular function after PTCA. The study group consisted of 30 patients in whom a contrast left ventricular angiogram and PTCA were performed after a first myocardial infarction. The centerline method was used to calculate dysfunction extent at baseline and its variation during dobutamine infusion at 7.5 microg/kg/min; contractile reserve was defined as a significant (> or = 15%) reduction of dysfunction extent. A second ventricular angiogram was performed 6 months later in all patients. Abnormal wall motion extent decreased at 6 months after PTCA (84+/-21% vs 70+/-29%, p = 0.0001). Wall motion improvement after PTCA correlated with the response to dobutamine (r = 0.54, p = 0.002). Ten patients showed a significant reduction (> or = 15%) of dysfunction extent at 6 months; dobutamine testing had a 80% sensitivity, 84% specificity, 67% positive predictive value, and 89% negative predictive value in detecting regional function improvement. In the subgroup of 21 patients without restenosis, both the correlation between dysfunction improvement after PTCA and response to dobutamine (r = 0.72, p = 0.0001) and the accuracy of dobutamine testing (sensitivity 88%, specificity 92%, positive predictive value 88%, and negative predictive value 92%) increased. The ejection fraction significantly increased (>5%) after PTCA in 6 patients; dobutamine testing had a 67% sensitivity, 74% specificity, 44% positive predictive value, and 88% negative predictive value in predicting the increase in the ejection fraction. In the subgroup without restenosis the improvement of the ejection fraction correlated with the response to dobutamine (r = 0.63, p = 0.007), and the sensitivity of dobutamine testing was 80%, specificity 83%, positive predictive value 67%, and negative predictive value 91%. In conclusion, dobutamine contrast left ventriculography testing in the same session as coronary angiography predicts regional function and ejection fraction improvement after PTCA in postinfarction patients, particularly when restenosis does not develop.

[Determinants of contractile reserve in the infarction area. A quantitative study using dobutamine in contrast left ventriculography]. / Determinantes de la reserva contráctil en la zona del infarto. Estudio cuantitativo mediante ventriculografía de contraste con dobutamina.

AIM: The aim of this study was to relate the contractile reserve in infarction segments to the dysfunction at rest and to the residual coronary stenosis. METHODS: The study group consisted of 95 patients with a first myocardial infarction. Contrast left ventricular at baseline and after dobutamine infusion at 7.5 microg/kg/min and coronary angiograms were performed. The centerline method was used to quantify the extent of dysfunction (percentage of chords with dysfunction in the territory of the infarction artery) and its maximum severity (maximum units of standard deviation [SD] below the normal wall motion reference). Reduction of dysfunction extent with dobutamine was measured. RESULTS: On increasing baseline dysfunction severity, both the magnitude of the response to dobutamine ( 2 SD 3 SD 4 SD +/- 5 SD [n = 15] = 9+/-13%, > 5 SD [n = 13] = 3+/-4%, p = 0,0001), and the number of patients with a significant (> or =15%) positive response ( 2 SD 3 SD 4 SD 5 SD = 0%, p<0,0001) decreased. There were no differences in dobutamine improvement among the subgroups with (n = 84) or without (n = 11) significant stenosis in the infarction artery (18+/-15 vs. 16 +/-18%), or between the subgroups with a patent (n = 76, 18+/-19%) or occluded (n = 19, 11+/-11%) artery. CONCLUSIONS: Dobutamine response is related to dysfunction severity in the infarction area: when the severity is 5 (high negative response prevalence), dobutamine testing does not seem indicate. The existence of residual coronary stenosis does not attenuate contractile reserve at low dobutamine doses.

[Determination of ejection fraction and left ventricular fraction using isotopic ventriculography and bidimensional echocardiography. Comparison with contrast ventriculography]. / Determinación de la fracción de eyección y volúmenes del ventrículo izquierdo mediante ventriculografía isotópica y ecocardiografía bidimensional. Comparación con la ventriculografía de contraste.

OBJECTIVES: The aim of this study was to determine the correlation and agreement between the values of left ventricular ejection fraction and volumes assessed by echocardiography and radionuclide ventriculography with the results obtained by contrast angiography, as well as the variability of each method in these measurements. PATIENTS AND METHODS: In a group of 59 patients with a first acute myocardial infarction we have determined left ventricular ejection fraction and volumes by two-dimensional echocardiography, equilibrium radionuclide ventriculography and contrast angiography initially and six months after myocardial infarction. We also assess the variability in the determinations in these three methods. RESULTS: We found significant correlations in ejection fraction and volumes by radionuclide ventriculography and echocardiography with contrast angiography. The correlation was higher in ejection fraction and end-systolic volume by radionuclide ventriculography (r = 0.88 and r = 0.73) than by echocardiography (r = 0.55 and r = 0.63; p < 0.01), whereas the correlation of end-diastolic volume was moderate by both methods (r = 0.58 and r = 0.47), without significant differences. The agreement between contrast angiography and radionuclide ventriculography was higher, with narrower limits of agreement than between contrast angiography and echocardiography in ejection fraction as well as in ventricular volumes. We have found high and significant correlations between two determinations by each method in all parameters, although they were higher in ejection fraction by contrast angiography (r = 0.96) and radionuclide ventriculography (r = 0.98) than by echocardiography (r = 0.70; p < 0.01). The limits of agreement were always wider in echocardiography, narrower in contrast angiography and the narrowest in radionuclide ventriculography, showing its superior reproducibility. CONCLUSIONS: In this group of myocardial infarction patients, the variability in the measurements was lower by radionuclide ventriculography than by echocardiography, this could be the reason for overall better results found in correlation and agreement between radionuclide ventriculography and contrast angiography than between echocardiography and contrast angiography in the assessment of left ventricular ejection fraction and volumes.

Positive effect of CPAP treatment on the control of difficult-to-treat hypertension.

The aim of the present study was to analyse the role of continuous positive airway pressure (CPAP) treatment in patients with difficult-to-control hypertension (DC-HT) and sleep apnoea. An Autoset (ResMed, Sydney, Australia) study was performed in 60 patients diagnosed with DC-HT based on two 24-h ambulatory blood pressure monitorisation (ABPM) studies. CPAP was offered to patients with an apnoea/hypopnoea index (AHI) > or =15 events.h(-1). After 3 months of treatment, repeat ABPM was performed to evaluate the effect of CPAP upon the blood pressure values. A total of 39 (65%) patients received CPAP treatment, but only 33 completed the study. The mean+/-sd systolic and diastolic blood pressures (SBP and DBP, respectively) were 154.8+/-14 and 90+/-8.8 mmHg. Patients had a mean+/-sd AHI of 37.7+/-18.2 events.h(-1). Only three patients presented a dipper nocturnal pressure pattern. CPAP treatment significantly reduced SBP (-5.2 mmHg), and particularly the nocturnal values (-6.1 mmHg), but not DBP. Considering only those patients who tolerated CPAP, the decrease in SBP was greater (-7.3 mmHg). Furthermore, CPAP treatment significantly increased the percentage of patients who recovered the dipper pattern (three (9.1%) out of 33 versus 12 (36.4%) out of 33). Continuous positive airway pressure treatment significantly reduces systolic blood pressure, particularly at night, and normalises the nocturnal pressure pattern in patients with difficult-to-control hypertension and sleep apnoea.

Trastornos respiratorios durante el sueño en pacientes con hipertensión arterial de difícil control / Sleep-disordered breathing in patients with difficult-to-control hypertension

Objetivo: Analizar la relación existente entre los trastornos respiratorios durante el sueño y la hipertensión arterial de difícil control (HTAr). Pacientes y métodos: Se consideró HTAr cuando las cifras medias de la presión arterial sistólica (PAS) eran mayores o iguales a 125 mmHg y/o la diastólica (PAD) era igual o superior a 80 mmHg según el registro de 2 estudios de monitorización ambulatoria durante 24 h a pesar de la utilización de 3 o más fármacos antihipertensivos. Se realizó posteriormente una poligrafía respiratoria (Autoset) para el estudio de los trastornos respiratorios durante el sueño en todos los pacientes. Resultados: Se incluyó en el estudio a 49 pacientes con una media (± desviación estándar) de edad de 68,1 ± 9,1 años, PAS/PAD media de 152,5 ±13/89,2 ±8,5 mmHg y una media de 3,5 fármacos prescritos. El índice de apneas-hipopneas (IAH) fue de 26,2 ± 19,5, de predominio obstructivo. Los pacientes con síndrome de apneas-hipopneas durante el sueño (SAHS) grave (IAH ≥ 30; 40,8%) presentaron mayor descontrol de la PAS tanto diurna (p = 0,017) como nocturna (p = 0,033) que el resto de pacientes, así como mayor PAD diurna (p = 0,035) y toma de un mayor número de fármacos que quienes no lo presentaban (IAH < 10; 28,6%) (p = 0,041). Tomados en su conjunto, los pacientes presentaron una correlación significativa entre las cifras de la presión arterial y la obesidad, además de existir una correlación ajustada significativa con el IAH sólo en los pacientes con SAHS. El IAH se mostró como el predictor independiente que más influyó en las cifras de la presión arterial de estos pacientes. Conclusiones: En pacientes con HTAr la prevalencia de SAHS fue muy elevada. En los pacientes con SAHS, el IAH se mostró como el factor predictivo independiente más importante de las cifras de presión arterial

Objective: To analyze the relationship between sleep-disordered breathing and difficult-to-control arterial hyper-tension. Patients and methods: Patients were considered to have difficult-to-control hypertension when mean systolic blood pressure was 125 mm Hg or higher and/or mean diastolic blood pressure was more than or equal to 80 mm Hg (as recorded during 2 24-hour ambulatory monitoring studies) despite the use of 3 or more antihypertensive drugs. Respiratory polygraphy using the AutoSet device (ResMed Corp, Sydney, Australia) was then performed to study sleep-disordered breathing in all patients. Results: Forty-nine patients with a mean (SD) age of 68.1 (9.1) years, mean systolic and diastolic pressures of 152.5 (13)/89.2 (8.5) mm Hg, and an average of 3.5 prescribed drugs were included in the study. The mean apnea-hypopnea index (AHI) was 26.2 (19.5) and events were predominantly obstructive. Patients with severe sleep apnea-hypopnea syndrome (SAHS) (AHI ≥ 30; 40.8%) showed more uncontrolled daytime (P=.017) and nighttime (P=.033) systolic pressure than the rest, as well as higher daytime diastolic pressure (P=.035) and a greater consumption of drugs than those without severe SAHS (AHI < 10; 28.6%) (P=.041). The study population as a whole showed a significant correlation between blood pressure and obesity. There was a significant correlation (adjusted for age and sex) with AHI only in patients with SAHS. AHI was found to be the independent predictor with the greatest effect on blood pressure in these patients. Conclusions: Prevalence of SAHS was very high in patients with difficult-to-control hypertension. In patients with SAHS, AHI was found to be the independent predictor with the greatest affect on arterial blood pressure