Cuffless Blood Pressure Devices.

Hypertension is associated with more end-organ damage, cardiovascular events, and disability-adjusted life years lost in the United States compared with all other modifiable risk factors. Several guidelines and scientific statements now endorse the use of out-of-office blood pressure (BP) monitoring with ambulatory BP monitoring or home BP monitoring to confirm or exclude hypertension status based on office BP measurement. Current ambulatory or home BP monitoring devices have been reliant on the placement of a BP cuff, typically on the upper arm, to measure BP. There are numerous limitations to this approach. Cuff-based BP may not be well-tolerated for repeated measurements as is utilized with ambulatory BP monitoring. Furthermore, improper technique, including incorrect cuff placement or use of the wrong cuff size, may lead to erroneous readings, affecting diagnosis and management of hypertension. Compared with devices that utilize a cuff, cuffless BP devices may overcome challenges related to technique, tolerability, and overall utility in the outpatient setting. However, cuffless devices have several potential limitations that limit its routine use for the diagnosis and management of hypertension. The review discusses the different approaches for determining BP using various cuffless devices including engineering aspects of cuffless device technologies, validation protocols to test accuracy of cuffless devices, potential barriers to widespread implementation, and future areas of research. This review is intended for the clinicians who utilize out-of-office BP monitoring for the diagnosis and management of hypertension.

Short-Term Reproducibility of Masked Hypertension Among Adults Without Office Hypertension.

The 2017 American College of Cardiology/American Heart Association blood pressure (BP) Hypertension Clinical Practice Guidelines recommends ambulatory BP monitoring to detect masked hypertension. Data on the short-term reproducibility of masked hypertension are scarce. The IDH study (Improving the Detection of Hypertension) enrolled 408 adults not taking antihypertensive medication from 2011 to 2013. Office BP and 24-hour ambulatory BP monitoring were performed on 2 occasions, a median of 29 days apart. After excluding participants with office hypertension (mean systolic BP ≥130 mm Hg or diastolic BP ≥80 mm Hg), the analytical sample included 254 participants. Using the κ statistic, we evaluated the reproducibility of masked awake hypertension (awake systolic/diastolic BP ≥130/80 mm Hg) defined by the 2017 BP guideline thresholds, as well as masked 24-hour (24-hour systolic/diastolic BP ≥125/75 mm Hg), masked asleep (asleep systolic/diastolic BP ≥110/65 mm Hg), and any masked hypertension (high awake, 24-hour, and asleep BP). The mean (SD) age of participants was 38.0 (12.3) years and 65.7% were female. Based on the first and second ambulatory BP recordings, 24.0% and 26.4% of participants, respectively, had masked awake hypertension. The κ statistic (95% CI) was 0.50 (0.38-0.62) for masked awake, 0.57 (0.46-0.69) for masked 24-hour, 0.57 (0.47-0.68) for masked asleep, and 0.58 (0.47-0.68) for any masked hypertension. Clinicians should consider the moderate short-term reproducibility of masked hypertension when interpreting the results from a single ambulatory BP recording.

Ambulatory Blood Pressure Phenotypes in Adults Taking Antihypertensive Medication with and without CKD.

BACKGROUND AND OBJECTIVES: Recent guidelines recommend out-of-clinic BP measurements. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We compared the prevalence of BP phenotypes between 561 black patients, with and without CKD, taking antihypertensive medication who underwent ambulatory BP monitoring at baseline (between 2000 and 2004) in the Jackson Heart Study. CKD was defined as an albumin-to-creatinine ratio ≥30 mg/g or eGFR <60 ml/min per 1.73 m2. Sustained controlled BP was defined by BP at goal both inside and outside of the clinic and sustained uncontrolled BP as BP above goal both inside and outside of the clinic. Masked uncontrolled hypertension was defined by controlled clinic-measured BP with uncontrolled out-of-clinic BP. RESULTS: CKD was associated with a higher multivariable-adjusted prevalence ratio for uncontrolled versus controlled clinic BP (prevalence ratio, 1.44; 95% CI, 1.02 to 2.02) and sustained uncontrolled BP versus sustained controlled BP (prevalence ratio, 1.66; 95% CI, 1.16 to 2.36). There were no statistically significant differences in the prevalence of uncontrolled daytime or nighttime BP, nondipping BP, white-coat effect, and masked uncontrolled hypertension between participants with and without CKD after multivariable adjustment. After multivariable adjustment, reduced eGFR was associated with masked uncontrolled hypertension versus sustained controlled BP (prevalence ratio, 1.42; 95% CI, 1.00 to 2.00), whereas albuminuria was associated with uncontrolled clinic BP (prevalence ratio, 1.76; 95% CI, 1.20 to 2.60) and sustained uncontrolled BP versus sustained controlled BP (prevalence ratio, 2.02; 95% CI, 1.36 to 2.99). CONCLUSIONS: The prevalence of BP phenotypes defined using ambulatory BP monitoring is high among adults with CKD taking antihypertensive medication.

Associations of awake and asleep blood pressure and blood pressure dipping with abnormalities of cardiac structure: the Coronary Artery Risk Development in Young Adults study.

OBJECTIVES: To evaluate the associations of high awake blood pressure (BP), high asleep BP, and nondipping BP, determined by ambulatory BP monitoring (ABPM), with left ventricular hypertrophy (LVH) and geometry. METHODS: Black and white participants (n = 687) in the Coronary Artery Risk Development in Young Adults study underwent 24-h ABPM and echocardiography at the Year 30 Exam in 2015-2016. The prevalence and prevalence ratios of LVH were calculated for high awake SBP (≥130 mmHg), high asleep SBP (≥110 mmHg), the cross-classification of high awake and asleep SBP, and nondipping SBP (percentage decline in awake-to-asleep SBP < 10%). Odds ratios for abnormal left ventricular geometry associated with these phenotypes were calculated. RESULTS: Overall, 46.0 and 49.1% of study participants had high awake and asleep SBP, respectively, and 31.1% had nondipping SBP. After adjustment for demographics and clinical characteristics, high awake SBP was associated with a prevalence ratio for LVH of 2.79 [95% confidence interval (95% CI) 1.63-4.79]. High asleep SBP was also associated with a prevalence ratio for LVH of 2.19 (95% CI 1.25-3.83). There was no evidence of an association between nondipping SBP and LVH (prevalence ratio 0.70, 95% CI 0.44-1.12). High awake SBP with or without high asleep SBP was associated with a higher odds ratio of concentric remodeling and hypertrophy. CONCLUSION: Awake and asleep SBP, but not the decline in awake-to-asleep SBP, were associated with increased prevalence of cardiac end-organ damage.

Sex differences in masked hypertension: the Coronary Artery Risk Development in Young Adults study.

OBJECTIVE: To evaluate the association of sex with masked hypertension, defined by out-of-clinic hypertension based on ambulatory blood pressure monitoring (ABPM) among adults without hypertension based on blood pressure (BP) measured in the clinic, after adjusting for potential confounders. METHODS: We evaluated sex differences in the prevalence of masked hypertension and the difference between awake, or alternatively 24-h, ambulatory BP and clinic BP using multivariable adjusted models among 658 participants who underwent 24-h ABPM and had clinic SBP/DBP less than 140/90 mmHg during the Year 30 Exam of the Coronary Artery Risk Development in Young Adults study. RESULTS: The mean age ±â€Šstandard deviation (SD) of the participants was 54.8 ±â€Š3.7 years, 58.4% were women, and 58.2% were black. The prevalence of any masked hypertension was 37.5% among women and 60.6% among men. In a model including adjustment for demographics, cardiovascular risk factors, antihypertensive medication, and clinic BP, the prevalence ratios (95% confidence intervals) comparing men versus women were 1.39 (1.18-1.63) for any masked hypertension, and 1.60 (1.28-1.99), 1.71 (1.36-2.15), and 1.40 (1.13-1.73) for masked awake, 24-h and asleep hypertension, respectively. In a fully adjusted model, the differences between mean awake ambulatory BP and clinic BP were 2.75 [standard error (SE) 0.92] mmHg higher for SBP and 3.61 (SE 0.58) mmHg higher for DBP among men compared with women. CONCLUSION: The prevalence of masked hypertension on ABPM was high in both men and women. Male sex was an independent predictor of masked hypertension.

Race and sex differences in asleep blood pressure: The Coronary Artery Risk Development in Young Adults (CARDIA) study.

Nocturnal hypertension and non-dipping blood pressure are each associated with increased risk of cardiovascular disease. We determined differences in nocturnal hypertension and non-dipping systolic/diastolic blood pressure among black and white men and women who underwent 24-hour ambulatory blood pressure monitoring at the Coronary Artery Risk Development in Young Adults study Year 30 Exam in 2015-2016. Asleep and awake periods were determined from actigraphy complemented by sleep diaries. Nocturnal hypertension was defined as mean asleep systolic/diastolic blood pressure ≥ 120/70 mm Hg. Non-dipping systolic and diastolic blood pressure, separately, were defined as a decline in awake-to-asleep blood pressure < 10%. Among 767 participants, the prevalence of nocturnal hypertension was 18.4% and 44.4% in white and black women, respectively, and 36.4% and 59.9% in white and black men, respectively. After multivariable adjustment and compared with white women, the prevalence ratio (95% confidence interval) for nocturnal hypertension was 1.65 (1.18-2.32) for black women, 1.63 (1.14-2.33) for white men, and 2.01 (1.43-2.82) for black men. The prevalence of non-dipping systolic blood pressure was 21.5% and 41.0% in white and black women, respectively, and 20.2% and 37.9% in white and black men, respectively. Compared with white women, the multivariable-adjusted prevalence ratio (95% confidence interval) for non-dipping systolic blood pressure was 1.66 (1.18-2.32), 0.91 (0.58-1.42) and 1.66 (1.15-2.39) among black women, white men, and black men, respectively. Non-dipping diastolic blood pressure did not differ by race-sex groups following multivariable adjustment. In conclusion, black women and men have a high prevalence of nocturnal hypertension and non-dipping systolic blood pressure.

Implantable Cardioverter-defibrillator Therapy for Syncope: An Educational Example of a Multicomponent Electrocardiographic Differential Diagnosis and the Application of Clinical Trial Data to an Individual Patient.

This is a report of a patient with a history of hypertension and myocardial infarction and a left ventricular ejection fraction of 35% who suffered a syncopal event. Her admitting electrocardiogram was compatible with her old myocardial infarction, an anteroseptal left ventricular aneurysm, left ventricular hypertrophy, and short-QT syndrome. The present report discusses how each of these might contribute individually and to some extent synergistically to producing syncope. She was treated with an implantable cardioverter-defibrillator (ICD), though she did not meet strict Multicenter Automatic Defibrillator Implantation Trial (MADIT), MADIT II, and Multicenter Unsustained Tachycardia Trial (MUSTT) patient characteristics. Her implant, however, was consistent with the 2014 Heart Rhythm Society/American College of Cardiology/American Heart Association consensus document regarding patients who do not match clinical trial enrollees but for whom ICD consideration is appropriate.

Diagnosing Masked Hypertension Using Ambulatory Blood Pressure Monitoring, Home Blood Pressure Monitoring, or Both?

Guidelines recommend measuring out-of-clinic blood pressure (BP) to identify masked hypertension (MHT) defined by out-of-clinic BP in the hypertensive range among individuals with clinic-measured BP not in the hypertensive range. The aim of this study was to determine the overlap between ambulatory BP monitoring (ABPM) and home BP monitoring (HBPM) for the detection of MHT. We analyzed data from 333 community-dwelling adults not taking antihypertensive medication with clinic BP <140/90 mm Hg in the IDH study (Improving the Detection of Hypertension). Any MHT was defined by the presence of daytime MHT (mean daytime BP ≥135/85 mm Hg), 24-hour MHT (mean 24-hour BP ≥130/80 mm Hg), or nighttime MHT (mean nighttime BP ≥120/70 mm Hg). Home MHT was defined as mean BP ≥135/85 mm Hg on HBPM. The prevalence of MHT was 25.8% for any MHT and 11.1% for home MHT. Among participants with MHT on either ABPM or HBPM, 29.5% had MHT on both ABPM and HBPM; 61.1% had MHT only on ABPM; and 9.4% of participants had MHT only on HBPM. After multivariable adjustment and compared with participants without MHT on ABPM and HBPM, those with MHT on both ABPM and HBPM and only on ABPM had a higher left ventricular mass index (mean difference [SE], 12.7 [2.9] g/m2, P<0.001; and 4.9 [2.1] g/m2, P=0.022, respectively), whereas participants with MHT only on HBPM did not have an increased left ventricular mass index (mean difference [SE], -1.9 [4.8] g/m2, P=0.693). These data suggest that conducting ABPM will detect many individuals with MHT who have an increased cardiovascular disease risk.

Feed-forward active contour analysis for improved brachial artery reactivity testing.

The object of this study was to utilize a novel feed-forward active contour (FFAC) algorithm to find a reproducible technique for analysis of brachial artery reactivity. Flow-mediated dilation (FMD) is an important marker of vascular endothelial function but has not been adopted for widespread clinical use given its technical limitations, including inter-observer variability and differences in technique across clinical sites. We developed a novel FFAC algorithm with the goal of validating a more reliable standard. Forty-six healthy volunteers underwent FMD measurement according to the standard technique. Ultrasound videos lasting 5-10 seconds each were obtained pre-cuff inflation and at minutes 1 through 5 post-cuff deflation in longitudinal and transverse views. Automated segmentation using the FFAC algorithm with initial boundary definition from three different observers was used to analyze the images to measure diameter/cross-sectional area over the cardiac cycle. The %FMD was calculated for average, minimum, and maximum diameters/areas. Using the FFAC algorithm, the population-specific coefficient of variation (CV) at end-diastole was 3.24% for transverse compared to 9.96% for longitudinal measurements; the subject-specific CV was 15.03% compared to 57.41%, respectively. For longitudinal measurements made via the conventional method, the population-specific CV was 4.77% and subject-specific CV was 117.79%. The intraclass correlation coefficient (ICC) for transverse measurements was 0.97 (95% CI: 0.95-0.98) compared to 0.90 (95% CI: 0.84-0.94) for longitudinal measurements with FFAC and 0.72 (95% CI: 0.51-0.84) for conventional measurements. In conclusion, transverse views using the novel FFAC method provide less inter-observer variability than traditional longitudinal views. Improved reproducibility may allow adoption of FMD testing in a clinical setting. The FFAC algorithm is a robust technique that should be evaluated further for its ability to replace the more limited conventional technique for measurement of FMD.

Partnership for sustainability in cardiac surgery to address critical rheumatic heart disease in sub-Saharan Africa: the experience from Rwanda.

IMPORTANCE: Rheumatic heart disease (RHD) in the developing world results in critical disability among children, adolescents, and young adults-marginalizing a key population at its peak age of productivity. Few regions in sub-Saharan Africa have independently created an effective strategy to detect and treat streptococcal infection and mitigate its progression to RHD. OBJECTIVE: We describe a unique collaboration, where the Rwanda Ministry of Health, the Rwanda Heart Foundation, and an expatriate humanitarian cardiac surgery program have together leveraged an innovative partnership as a means to expand Rwanda's current capacity to address screening and primary prevention, as well as provide life-saving cardiac surgery for patients with critical RHD. EVIDENCE REVIEW: Interviews with key personnel and review of administrative records were conducted to obtain qualitative and quantitative data on the recruitment of clinical personnel, procurement of equipment, and program finances. The number of surgical cases completed and the resultant clinical outcomes are reviewed. FINDINGS: From 2008 to 2013, six annual visits were completed. A total of 128 prosthetic valves have been implanted in 86 complex patients in New York Heart Association (NYHA) class III or IV heart failure, with excellent clinical outcomes (5 % 30-day mortality). Postoperative complications included a cerebrovascular accident (n = 1) and hemorrhage, requiring reoperation (n = 2). All procedures were performed with participation of local personnel. CONCLUSIONS AND RELEVANCE: This strategy provides a reliable and consistent model of sophisticated specialty care delivery; inclusive of patient-centered cardiac surgery, mentorship, didactics, skill transfer, and investment in a sustainable cardiac program to address critical RHD in sub-Saharan Africa.