Background Programs targeting the standard modifiable cardiovascular risk factors (SMuRFs: hypertension, diabetes mellitus, hypercholesterolemia, smoking) are critical to tackling coronary heart ...disease at a community level. However, myocardial infarction in SMuRF-less individuals is not uncommon. This study uses 2 sequential large, multicenter registries to examine the proportion and outcomes of SMuRF-less ST-segment-elevation myocardial infarction (STEMI) patients. Methods and Results We identified 3081 STEMI patients without a prior history of cardiovascular disease in the Australian GRACE (Global Registry of Acute Coronary Events) and CONCORDANCE (Cooperative National Registry of Acute Coronary Syndrome Care) registries, encompassing 42 hospitals, between 1999 and 2017. We examined the proportion that were SMuRF-less as well as outcomes. The primary outcome was in-hospital mortality, and the secondary outcome was major adverse cardiovascular events (death, myocardial infarction, or heart failure, during the index admission). Multivariate regression models were used to identify predictors of major adverse cardiovascular events. Of STEMI patients without a prior history of cardiovascular disease 19% also had no history of SMuRFs. This proportion increased from 14% to 23% during the study period (
=0.0067). SMuRF-less individuals had a higher in-hospital mortality rate than individuals with 1 or more SMuRFs. There were no clinically significant differences in major adverse cardiovascular events at 6 months between the 2 groups. Conclusions A substantial and increasing proportion of STEMI presentations occur independently of SMuRFs. Discovery of new markers and mechanisms of disease beyond standard risk factors may facilitate novel preventative strategies. Studies to assess longer-term outcomes of SMuRF-less STEMI patients are warranted.
Hypertension (HTN) is the single greatest cardiovascular risk factor worldwide. HTN management is usually guided by brachial cuff blood pressure (BP), but questions have been raised regarding ...accuracy.
This comprehensive analysis determined the accuracy of cuff BP and the consequent effect on BP classification compared with intra-arterial BP reference standards.
Three individual participant data meta-analyses were conducted among studies (from the 1950s to 2016) that measured intra-arterial aortic BP, intra-arterial brachial BP, and cuff BP.
A total of 74 studies with 3,073 participants were included. Intra-arterial brachial systolic blood pressure (SBP) was higher than aortic values (8.0 mm Hg; 95% confidence interval CI: 5.9 to 10.1 mm Hg; p < 0.0001) and intra-arterial brachial diastolic BP was lower than aortic values (-1.0 mm Hg; 95% CI: -2.0 to -0.1 mm Hg; p = 0.038). Cuff BP underestimated intra-arterial brachial SBP (-5.7 mm Hg; 95% CI: -8.0 to -3.5 mm Hg; p < 0.0001) but overestimated intra-arterial diastolic BP (5.5 mm Hg; 95% CI: 3.5 to 7.5 mm Hg; p < 0.0001). Cuff and intra-arterial aortic SBP showed a small mean difference (0.3 mm Hg; 95% CI: -1.5 to 2.1 mm Hg; p = 0.77) but poor agreement (mean absolute difference 8.0 mm Hg; 95% CI: 7.1 to 8.9 mm Hg). Concordance between BP classification using the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure cuff BP (normal, pre-HTN, and HTN stages 1 and 2) compared with intra-arterial brachial BP was 60%, 50%, 53%, and 80%, and using intra-arterial aortic BP was 79%, 57%, 52%, and 76%, respectively. Using revised intra-arterial thresholds based on cuff BP percentile rank, concordance between BP classification using cuff BP compared with intra-arterial brachial BP was 71%, 66%, 52%, and 76%, and using intra-arterial aortic BP was 74%, 61%, 56%, and 65%, respectively.
Cuff BP has variable accuracy for measuring either brachial or aortic intra-arterial BP, and this adversely influences correct BP classification. These findings indicate that stronger accuracy standards for BP devices may improve cardiovascular risk management.
Reservoir pressure parameters eg, reservoir pressure (RP) and excess pressure (XSP) are biomarkers derived from blood pressure (BP) waveforms that have been shown to predict cardiovascular events ...independent of conventional cardiovascular risk markers. However, whether RP and XSP can be derived non‐invasively from operator‐independent cuff device measured brachial or central BP waveforms has never been examined. This study sought to achieve this by comparison of cuff reservoir pressure parameters with intra‐aortic reservoir pressure parameters. 162 participants (aged 61 ± 10 years, 72% male) undergoing coronary angiography had the simultaneous measurement of cuff BP waveforms (via SphygmoCor XCEL, AtCor Medical) and intra‐aortic BP waveforms (via fluid‐filled catheter). RP and XSP derived from cuff acquired brachial and central BP waveforms were compared with intra‐aortic measures. Concordance between brachial‐cuff and intra‐aortic measurement was moderate‐to‐good for RP peak (36 ± 11 vs 48 ± 14 mm Hg, P < 0.001; ICC 0.77, 95% CI: 0.71‐0.82), and poor‐to‐moderate for XSP peak (28 ± 10 vs 24 ± 9 mm Hg, P < 0.001; ICC 0.49, 95% CI: 0.35‐0.60). Concordance between central‐cuff and intra‐aortic measurement was moderate‐to‐good for RP peak (35 ± 9 vs 46 ± 14 mm Hg, P < 0.001; ICC 0.77, 95% CI: 0.70‐0.82), but poor for XSP peak (12 ± 3 vs 24 ± 9 mm Hg, P < 0.001; ICC 0.12, 95% CI: −0.13 to 0.31). In conclusion, both brachial‐cuff and central‐cuff methods can reasonably estimate intra‐aortic RP, whereas XSP can only be acceptably derived from brachial‐cuff BP waveforms. This should enable widespread application to determine the clinical significance, but there is significant room for refinement of the method.
Blood pressure (BP) is a leading global risk factor. Increasing age is related to changes in cardiovascular physiology that could influence cuff BP measurement, but this has never been examined ...systematically and was the aim of this study. Cuff BP was compared with invasive aortic BP across decades of age (from 40 to 89 years) using individual-level data from 31 studies (1674 patients undergoing coronary angiography) and 22 different cuff BP devices (19 oscillometric, 1 automated auscultation, 2 mercury sphygmomanometry) from the Invasive Blood Pressure Consortium. Subjects were aged 64±11 years, and 32% female. Cuff systolic BP overestimated invasive aortic systolic BP in those aged 40 to 49 years, but with each older decade of age, there was a progressive shift toward increasing underestimation of aortic systolic BP (
<0.0001). Conversely, cuff diastolic BP overestimated invasive aortic diastolic BP, and this progressively increased with increasing age (
<0.0001). Thus, there was a progressive increase in cuff pulse pressure underestimation of invasive aortic PP with increasing decades of age (
<0.0001). These age-related trends were observed across all categories of BP control. We conclude that cuff BP as an estimate of aortic BP was substantially influenced by increasing age, thus potentially exposing older people to greater chance for misdiagnosis of the true risk related to BP.
Though not a survey of Bertolt Brecht's poetry, this book covers the major periods in his work and most of its major themes as well. Each of the seven chapters deals with a segment from Brecht's ...considerably poetic opus. A central characteristic of Brecht's poetry is its dual function, as self-revelation and self-concealment. This emerges most clearly in the poet's relationship to his reader for whom Brecht dons a variety of guises, plays a variety of roles, and speaks in a variety of voices.
Thomson's methodology is pluralist, although he includes a discussion of how reader-response theory can be harnessed to the task of interpreting Brecht's poetry. Various means of interpretation and analysis are used, depending on which seems to yield the most information and insight. The only reading of Brecht's poetry categorically refused is the one that accepts it at face value as a record of Brecht's life experience. Despite outward appearances, Brecht is a devious writer, and nowhere more so than in his poetry, where he most immediately presents himself to his public.
Background
Numerous devices purport to measure central aortic BP as distinct from conventional brachial BP. This study aimed to determine the accuracy (validation) of the Sphygmocor Xcel-cuff device ...(AtCor Medical, Sydney, Australia) for measuring central BP.
Methods
330 patients (mean age 61.3 ± 10.6 years) undergoing coronary angiography had simultaneous measurement of invasive aortic BP and non-invasive cuff-derived central BP using the Xcel device (total
n
= 552 individual comparisons). Methods were undertaken according to Artery Society guidelines and several calibration techniques to derive central SBP were examined.
Results
Central SBP was significantly underestimated, and with wide variability, when using the default calibration of brachial cuff SBP/DBP (−7.7 ± 11.0 mmHg). Similar wide variability was observed using other calibration methods (cuff 33% form-factor MAP/DBP, −4.4 ± 11.5 mmHg; cuff 40% form-factor MAP/DBP, 4.7 ± 11.9 mmHg; cuff oscillometric MAP/DBP, −18.2 ± 12.1 mmHg). Only calibration with invasive aortic integrated MAP/DBP resulted in a mean difference ± SD (3.3 ± 7.5 mmHg) within the minimum tolerable error of ≤5 ± ≤8 mmHg. The difference between brachial cuff SBP and invasive aortic SBP was 3.3 ± 10.7 mmHg. A subsample (
n
= 151) analysis to determine the accuracy of central-to-brachial SBP amplification, showed this to be over-estimated by the Xcel device (4.3 ± 9.1 mmHg,
p
= 0.02).
Conclusion
Irrespective of calibration technique, the Sphygmocor Xcel-cuff device does not pass the Artery Society accuracy (validation) criteria for non-invasive measurement of central BP. Further accuracy refinements of this device are required.
Background
Accurate measurement of cuff systolic BP (SBP) and diastolic BP (DBP) is contingent on the assumption of oscillometric MAP being accurate. If MAP is inaccurate this is likely to impact the ...accuracy of cuff SBP and DBP, but this has never been determined and was the aim of the study.
Methods
In five independent studies, MAP was measured by five unique cuff oscillometric BP devices at the same time as invasive aortic MAP (area under the waveform) by fluid-filled or solid-state catheters among 262 patients (61 ± 11 years, 65% male) during coronary angiography. Cuff SBP and DBP were estimated by device-specific algorithms. Measurement errors were calculated as cuff — invasive aortic BP.
Results
For each BP device, MAP error was −2.6 ± 6.1, 0.76 ± 7.2, 1.4 ± 5.5, 1.5 ± 6.7 and 7.1 ± 9.2 mmHg. Corresponding SBP errors were 4.4 ± 8.7, −0.8 ± 11.2, −8.8 ± 10.4, −0.9 ± 10.5 and 1.9 ± 10.8 mmHg, whereas DBP errors were 8.8 ± 5.1, 2.0 ± 7.4, 6.7 ± 7.3, 10.3 ± 9.0 and 13.1 ± 6.4 mmHg. There was a direct relationship between errors in oscillometric MAP and SBP error in four of the five devices (
B
range = 0.42 to 1.04). However, MAP error was consistently related to DBP error in all devices (
B
range = 0.48 to 0.97). Across all devices, absolute error in MAP ≥3 mmHg corresponded to absolute error in SBP and DBP ≥5 mmHg in 56–77% and 62–88% of patients.
Conclusion
Errors in oscillometric MAP are directly related to cuff SBP and DBP inaccuracy, but the magnitude of error is device-specific. Further work is required to understand algorithms used in oscillometric devices to improve cuff BP accuracy.
Background
Cuff blood pressure (BP) is intended to approximate central aortic BP and accuracy is paramount. Sex differences in BP physiology could influence the accuracy of cuff BP as an estimate of ...invasive aortic BP, but this has not been explored in-depth and was the aim of this study.
Methods
Cuff and invasive aortic BP were measured in 1701 subjects (31.9% female, aged 63 ± 12) during coronary angiography from the INvaSive blood PressurE ConsorTium (INSPECT) database. Cuff accuracy was defined as cuff–invasive BP. In a sub-sample (
n
= 376, 27% female, aged 63 ± 11), invasive brachial BP was recorded to assess systolic (SBP) amplification (invasive brachial–aortic SBP).
Results
Invasive aortic SBP was higher in females compared with males (mean 95% CI: 141.8 mmHg 137.1, 146.3 versus 132.9 mmHg 129.4, 136.4,
p
< 0.001). Cuff SBP significantly underestimated invasive aortic SBP in females compared with males (−3.1 mmHg −5.9, −0.2 versus 1.4 mmHg −1.1, 4.0,
p
< 0.001 for difference). Sex differences remained after adjustment for age and height. In the sub-sample, aortic-to-brachial SBP-amplification was lower in females (7.1 mmHg 3.3, 10.8 versus 10.2 mmHg 5.1, 15.4,
p
= 0.0070). Sex, SBP-amplification, height and age were associated with cuff BP inaccuracy, but only SBP-amplification and age remained associated in multivariable analysis (
p
< 0.05).
Conclusion
Females have greater propensity towards cuff BP inaccuracy through underestimation of aortic SBP. Both age and the magnitude of aortic-to-brachial SBP-amplification are related to cuff BP inaccuracy, which provide greater understanding of sex differences in BP physiology and may help improve the accuracy of cuff BP methods.
Background
Exaggerated blood pressure (BP) during submaximal exercise independently predicts cardiovascular mortality and identifies uncontrolled high BP not detected at rest. However, thresholds for ...submaximal exercise BP during clinical exercise testing have never been defined from a large representative sample, which was the aim of this study.
Methods
Records from 13,949 people referred for a clinical exercise stress test (aged 52 ± 13 years, 61% male) using the Bruce treadmill protocol (stages 1 to 4 plus peak) were extracted from 4 Australian hospitals over the years 2000–2018. Exercise records were linked to administrative health datasets (hospital admissions and emergency presentations) to define clinical characteristics, including cardiovascular disease history. Thresholds denoting exaggerated BP were defined as > 90th centile at each exercise stage.
Results
SBP and DBP thresholds across all stages were higher in males vs. females (stage-1: 180/90 vs 175/90 mmHg; stage-2: 196/94 vs 190/90 mmHg; stage-3: 204/97 vs 196/91 mmHg; stage-4: 210/100 vs 196/92 mmHg; peak: 215/100 vs 206/95 mmHg). SBP at all stages increased stepwise from the 1st to 4th age quartile (
p
< 0.05), whilst DBP remained similar (stage-1: 163/90 to 185/92 mmHg; stage-2: 180/90 to 204/95 mmHg; stage-3: 193/90 to 210/95 mmHg, stage-4: 200/91, to 210/96 mmHg; peak: 201/95 to 217/100 mmHg). Results were similar irrespective of cardiovascular disease history.
Conclusion
This is the first study to define submaximal exercise BP thresholds during clinical exercise testing. Thresholds were higher in males compared to females and increased with age. These thresholds may help clinicians to identify people at increased high BP-related risk.
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