Upward shift of the lower range of coronary flow autoregulation in hypertensive patients with hypertrophy of the left ventricle

The lowest well tolerated blood pressure: A personalized target for all?

The optimal blood pressure (BP) target for prevention of cardiovascular complications of hypertension remains uncertain. Most Guidelines suggest different targets depending on age, comorbidities and treatment tolerability, but the underlying evidence is not strong. Results of randomized strategy trials comparing lower (i.e., more intensive) versus higher (i.e., less intensive) BP targets should drive the definition. However, these trials tested different BP targets based on systolic BP, diastolic BP or combined systolic and diastolic BP goals. Overall, the more intensive treatment targets reduced the risk of major cardiovascular complications of hypertension when compared with the less intensive targets, despite a higher incidence of unwanted effects including, but not limited to, hypotension, electrolyte abnormalities and renal dysfunction. Consequently, some Guidelines defined low BP thresholds (i.e., 120/70 mmHg) not to exceed downward because of the expectation that unwanted effects may outweigh the outcome benefits. The present review discusses the evidence underlying the choice of BP targets, which remains an important step in the management of hypertensive patients. We conclude that, on the ground of the heterogeneity of available data in support to fixed BP targets, their definition should be personalized in all patients and based on best trade-off between efficacy and safety, i.e., the lowest well tolerated BP.

Associations of short- and long-term mortality with admission blood pressure in Chinese patients with different heart failure subtypes

It remains unknown whether systolic (SBP) and diastolic (DBP) pressure on admission are associated with short- and long-term mortality in Chinese patients with heart failure with preserved (HFpEF), mildly reduced (HFmrEF), and reduced (HFrEF) ejection fraction. In 2706 HF patients (39.1% women; mean age, 68.8 years), we assessed the risk of 30-day, 1-year, and long-term (> 1 year) mortality with 1-SD increment in SBP and DBP, using multivariable logistic and Cox regression, respectively. During a median follow-up of 4.1 years, 1341 patients died. The 30-day, 1-year, and long-term mortality were 3.5%, 16.7%, and 39.4%, respectively. In multivariable-adjusted analyses additionally accounted for DBP or SBP, a higher SBP conferred a higher risk of long-term mortality (hazard ratio, 1.11; 95% CI, 1.02-1.22; p = .017) and a lower DBP was associated with a higher risk of all types of mortality (p ≤ .011) in all HF patients. Independent of potential confounders including DBP or SBP, in patients with HFpEF, higher SBP and lower DBP levels predicted a higher risk of long-term mortality with hazard ratios amounting to 1.16 (95% CI, 1.04-1.29; p = .007) and .89 (95% CI, .80-.99; p = .028), respectively. In patients with HFmrEF and HFrEF, irrespective of adjustments of potential confounders, DBP was associated with 1-year mortality with odds ratios ranging from .49 to .62 (p ≤ .006). In conclusion, lower DBP and higher SBP levels on admission were associated with a higher risk of different types of all-cause mortality in Chinese patients with different HF subtypes. Our observations highlight that admission BP may help to improve risk stratification.

Provisional Decision-Making for Perioperative Blood Pressure Management: A Narrative Review

Blood pressure (BP) is a basic determinant for organ blood flow supply. Insufficient blood supply will cause tissue hypoxia, provoke cellular oxidative stress, and to some extent lead to organ injury. Perioperative BP is labile and dynamic, and intraoperative hypotension is common. It is unclear whether there is a causal relationship between intraoperative hypotension and organ injury. However, hypotension surely compromises perfusion and causes harm to some extent. Because the harm threshold remains unknown, various guidelines for intraoperative BP management have been proposed. With the pending definitions from robust randomized trials, it is reasonable to consider observational analyses suggesting that mean arterial pressures below 65 mmHg sustained for more than 15 minutes are associated with myocardial and renal injury. Advances in machine learning and artificial intelligence may facilitate the management of hemodynamics globally, including fluid administration, rather than BP alone. The previous mounting studies concentrated on associations between BP targets and adverse complications, whereas few studies were concerned about how to treat and multiple factors for decision-making. Hence, in this narrative review, we discussed the way of BP measurement and current knowledge about baseline BP extracting for surgical patients, highlighted the decision-making process for BP management with a view to providing pragmatic guidance for BP treatment in the clinical settings, and evaluated the merits of an automated blood control system in predicting hypotension.

Increased mortality with intensive control in patients with higher baseline SBP and lower Framingham risk

OBJECTIVE

In the Systolic Blood Pressure Intervention Trial (SPRINT), the relative reduction in primary outcome with intensive blood pressure (BP) control was numerically smallest in the highest baseline SBP tertile. In this post hoc analysis of SPRINT, the goal was to explore whether the effects of intensive BP treatment varied among patients with different baseline SBP and cardiovascular risks.

METHODS

Patient-level data from 9361 randomized participants in SPRINT were used. Heterogeneity between treatment and patient characteristics were examined stratified by different baseline SBP levels. Cumulative incidences of primary outcome and all-cause death were compared between treatment groups for patients with baseline SBP at least 160 mmHg and lower Framingham risk.

RESULTS

For participants with a baseline SBP of at least 160 mmHg, intensive treatment was associated with a higher rate of all-cause death as compared with standard treatment (1.86 vs. 1.62% per year). After adjustment for age and sex, intensive treatment was associated with significantly increased all-cause death compared with standard treatment [hazard ratio (95% CI) for intensive group: 3.12 (1.00-9.69); P = 0.049] in participants with an SBP of at least 160 mmHg and a Framingham risk score of 31.3% or less (average of median and geometric mean). Patient outcomes were otherwise similar regarding age, use of antihypertensive therapy, cardiovascular disease or chronic kidney disease.

CONCLUSION

Among the SPRINT participants with a baseline SBP of at least 160 mmHg and a lower Framingham risk score, targeting an SBP of less than 120 mmHg compared with less than 140 mmHg resulted in a significantly higher rate of all-cause death.

The diastolic blood pressure J-curve revisited: An update

Hypertension remains a leading cause of morbidity and mortality. Recent treatment guidelines stress more strict systolic blood pressure (SBP) targets without regard for abnormally low achieved diastolic blood pressures (DBP). However, as DBP falls below a critical level, adverse events increase, the so-called J-shaped curve. Proponents argue that the low DBP is causative due to reduced coronary perfusion during diastole with obstructive coronary artery disease (CAD), whereas others postulate the J-curve represents reverse causality from underlying comorbidity. Most data are observational, derived from population-based cohorts or post-hoc analyses of randomized controlled trials (RCT) conducted for other reasons. The purpose of this review is to analyze the observational studies performed over the last decade addressing the J-curve, with consideration of earlier data. Overall, a J-curve exists, but it remains uncertain whether low DBP is causative or instead reflects reverse causation from either diseased vasculature (widened pulse pressure) or severe underlying comorbidity. The most convincing data for causation come from studies restricted to patients with documented CAD, with evidence suggesting revascularization may mitigate risk. RCTs are needed to determine if a low DBP should preclude intensification of therapy, especially with documented CAD. Firm recommendations cannot be made with contemporary data.

Intra-aortic Balloon Pump Use With Extra Corporeal Membrane Oxygenation-A Mock Circulation Loop Study

Venoarterial extracorporeal membrane oxygenation (ECMO) is used in cardiogenic shock refractory to inotropic support and intra-aortic balloon pump (IABP) support. Peripheral ECMO can lead to ventricular distention, and IABP can be used to mitigate these effects. The aim of this study was to quantify the effects of IABP concomitant with ECMO, under different simulated hemodynamic conditions in a mock circulatory loop. Different simulated states of isolated left ventricular (LV) failure and biventricular failure with graded LV failure severities were supported with ECMO and ECMO with IABP. The impact on left ventricular end-diastolic pressure (LVEDP), volume (LVEDV), coronary flow rate, and cerebral flow rate were evaluated. Left ventricular volumes and pressures increased from the heart failure states with the addition of ECMO. The IABP provided between 3% and 7% reductions in LVEDP and between 1% and 10% reductions in LVEDV. The addition of IABP had minimal effect on cerebral blood flow (0% to 7%), but the variable impact on coronary blood flow with increased diastolic coronary flow of 23% to 50%, but the reduction in mean coronary flow by up to 30%. The efficacy of the IABP was strongly related to ventricular contractility. This study demonstrates the need for careful IABP selection concomitant with ECMO.

Associations of Left Ventricular Structure and Function With Blood Pressure in Heart Failure With Preserved Ejection Fraction: Analysis of the TOPCAT Trial

Background

Data on the association of systolic and diastolic blood pressure with the structure and function of failing hearts with preserved ejection fraction (EF) are sparse.

Methods and Results

This analysis included 935 patients with heart failure (49.4% women; mean age, 69.9 years) with preserved EF (≥45%) enrolled in the TOPCAT (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist) Trial before initiation of randomized therapy. Left ventricular (LV) structure (dimensions, wall thickness, and mass index), diastolic function (left atrial volume index, transmitral blood flow, and mitral annular velocities), and systolic function (EF and longitudinal strain) were assessed echocardiographically. In multivariable‐adjusted analyses, association sizes expressed per 1‐SD (14.8–mm Hg) increment in systolic blood pressure were 0.020 cm (P=0.003) and 0.018 cm (P=0.004) for LV septal and posterior wall thickness, respectively, and 2.42 mg/m² (P=0.018) for LV mass index. The corresponding associations with diastolic blood pressure were nonsignificant (P≥0.067). In similarly adjusted analyses, the association sizes expressed per 1‐SD (10.7–mm Hg) increment in diastolic blood pressure were −0.15 for E/A (P<0.001), −0.76 for E/e′ (P=0.006), and −0.62% for EF (P=0.024). These findings were consistent, if models including systolic blood pressure were additionally adjusted for diastolic blood pressure and vice versa, albeit that the relation of EF with diastolic blood pressure weakened (−0.54%; P=0.10).

Conclusions

In diastolic heart failure, LV wall thickness and LV mass index increased with higher systolic blood pressure, but not with higher diastolic blood pressure, whereas functional measures reflecting diastolic LV function decreased with higher diastolic blood pressure, independent of systolic blood pressure. These observations highlight the importance of controlling both systolic and diastolic blood pressure as modifiable risk factors to reduce the risk of LV remodeling and diastolic LV dysfunction.

Baseline Diastolic Blood Pressure and Cardiovascular Outcomes in SPRINT Participants with Chronic Kidney Disease

Background

We sought to determine whether intensive systolic BP (SBP) lowering was harmful in Systolic Blood Pressure Intervention Trial (SPRINT) participants with CKD (eGFR<60 ml/min per 1.73 m2) and lower baseline diastolic BP (DBP).

Methods

We related baseline DBP with the SPRINT primary composite end point (myocardial infarction, acute coronary syndrome, stroke, acute decompensated heart failure, or cardiovascular death) and all-cause death. We examined the effect of intensive SBP lowering on these outcomes across the range of baseline DBPs using Cox regression with treatment by baseline DBP interaction terms.

Results

Among 2646 SPRINT participants with CKD, lower baseline DBP was associated with a higher adjusted hazard of the primary composite end point and all-cause death. For example, participants with baseline DBP of 61 mm Hg (mean baseline DBP in the lowest tertile) experienced a 37% (95% CI, 7% to 75%) higher hazard of the primary outcome relative to participants with baseline DBP of 75 mm Hg (mean baseline DBP for overall). The benefit of intensive SBP lowering was consistent across a range of baseline DBPs on rates of the primary composite end point (linear interaction P value =0.56) and all-cause death (linear interaction P value =0.20).

Conclusions

Among SPRINT participants with baseline CKD, lower DBP was associated with higher rates of the primary composite end point and all-cause death. However, DBP did not seem to modify the benefit of intensive SBP lowering on the primary composite end point or all-cause death. Our results suggest that lower DBP should not necessarily impede more intensive SBP lowering in patients with mild to moderate CKD.

An advanced mock circulation loop for in vitro cardiovascular device evaluation

Controlled and repeatable in vitro evaluation of cardiovascular devices using a mock circulation loop (MCL) is essential prior to in vivo or clinical trials. MCLs often consist of only a systemic circulation with no autoregulatory responses and limited validation. This study aimed to develop, and validate against human data, an advanced MCL with systemic, pulmonary, cerebral, and coronary circulations with autoregulatory responses. The biventricular MCL was constructed with pneumatically controlled hydraulic circulations with Starling responsive ventricles and autoregulatory cerebral and coronary circulations. Hemodynamic repeatability was assessed and complemented by validation using impedance cardiography data from 50 healthy humans. The MCL successfully simulated patient scenarios including rest, exercise, and left heart failure with and without cardiovascular device support. End-systolic pressure-volume relationships for respective healthy and heart failure conditions had slopes of 1.27 and 0.54 mm Hg mL^-1 (left ventricle), and 0.18 and 0.10 mm Hg mL^-1 (right ventricle), aligning with the literature. Coronary and cerebral autoregulation showed a strong correlation (R² : .99) between theoretical and experimentally derived circuit flow. MCL repeatability was demonstrated with correlation coefficients being statistically significant (P < .05) for all simulated conditions while MCL hemodynamics aligned well with human data. This advanced MCL is a valuable tool for inexpensive and controlled evaluation of cardiovascular devices.

Potential impact of the 2017 ACC/AHA guideline on high blood pressure in normotensive patients with stable coronary artery disease: insights from the CLARIFY registry

Aims

The 2017 American College of Cardiology/American Heart Association (ACC/AHA) guideline on high blood pressure (BP) lowered the threshold defining hypertension and BP target in high-risk patients to 130/80 mmHg. Patients with coronary artery disease and systolic BP 130–139 mmHg or diastolic BP 80–89 mmHg should now receive medication to achieve this target. We aimed to investigate the relationship between BP and cardiovascular events in ‘real-life’ patients with coronary artery disease considered as having normal BP until the recent guideline.

Methods and results

Data from 5956 patients with stable coronary artery disease, no history of hypertension or heart failure, and average BP <140/90 mmHg, enrolled in the CLARIFY registry (November 2009 to June 2010), were analysed. In a multivariable-adjusted Cox proportional hazards model, after a median follow-up of 5.0 years, diastolic BP 80–89 mmHg, but not systolic BP 130–139 mmHg, was associated with increased risk of the primary endpoint, a composite of cardiovascular death, myocardial infarction, or stroke (hazard ratio 2.15, 95% confidence interval 1.22–3.81 vs. 70–79 mmHg and 1.12, 0.64–1.97 vs. 120–129 mmHg). No significant increase in risk for the primary endpoint was observed for systolic BP <120 mmHg or diastolic BP <70 mmHg.

Conclusion

In patients with stable coronary artery disease defined as having normal BP according to the 140/90 mmHg threshold, diastolic BP 80–89 mmHg was associated with increased cardiovascular risk, whereas systolic BP 130–139 mmHg was not, supporting the lower diastolic but not the lower systolic BP hypertension-defining threshold and treatment target in coronary artery disease.

ClinicalTrials identifier

ISRCTN43070564.

The Ongoing Saga of Optimal Blood Pressure Level in Patients With Diabetes Mellitus and Coronary Artery Disease

See Article by White et al .

Prognostic significance of acute hypertensive response in ischemic stroke or transient ischemic attack patients and its relationship with left ventricular myocardial function

OBJECTIVES

Acute hypertensive response (AHR) in acute stroke is associated with adverse outcomes; however, the underlying pathophysiology of the association is poorly understood and its prognostic impact in ischemic stroke remains unclear. We aimed to investigate the prognostic significance of AHR in patients with ischemic stroke or transient ischemic attack (TIA), and further examined the relationship between AHR and myocardial function, using two-dimensional speckle-tracking echocardiography (2D-STE).

METHODS

A total of 244 consecutive patients with acute ischemic stroke (AIS) (n = 192) or TIA (n = 52), who were evaluated with 2D-STE within 7 days from admission, were retrospectively analysed. The primary endpoint was a composite of major adverse cardiovascular and cerebrovascular events (MACCE), including death, myocardial infraction or recurrent ischemic stroke.

RESULTS

Among the study population, AHR was observed in 161 (66%) patients. During a mean follow-up of 21.0 ± 12.5 months, 29 patients (11.9%) [25 (15.5%) AHR vs. 4 (4.8%) No AHR, P = 0.014] reached the primary endpoint. A Kaplan-Meier curve revealed that patients with AHR had a significantly higher incidence of MACCE than those without AHR (log-rank P = 0.013). Multivariate Cox regression analysis demonstrated that AHR [adjusted hazard ratio 4.60, 95% confidence interval (95% CI) 1.31-16.15] was a strong predictor of MACCE. In multivariate logistic regression analysis, left ventricular global longitudinal strain (per 1% decrease) showed a significant relationship with AHR (adjusted odds ratio 1.17, 95% CI 1.02-1.35).

CONCLUSION

AHR in patients with AIS or TIA may be an important poor prognostic marker related to myocardial dysfunction.

[Blood pressure targets in patients with diabetes mellitus : What are optimum values?]

Diabetes mellitus and arterial hypertension are the most prevalent diseases in the aging population. Both are important risk factors for the development of cardiovascular complications and are associated with a high mortality. Both diseases are often first recognized late. The prognosis of patients with diabetes mellitus is favorably influenced by an optimal adjustment of blood sugar and blood pressure, as confirmed in large randomized clinical trials. Patients with diabetes mellitus and a blood pressure >130/80 mm Hg should first receive life style counseling with respect to nutrition and activity. Drug treatment for reduction of blood pressure is recommended for a blood pressure ≥140/90 mm Hg.

In-Vitro Evaluation of Cardiac Energetics and Coronary Flow with Volume Displacement and Rotary Blood Pumps

Bridge to recovery with left ventricular assist device (LVAD) support has been more prominent with volume displacement pumps (VDPs) than with rotary blood pumps (RBPs), which may be due to VDPs providing greater ventricular unloading and coronary artery flow. To compare ventricular unloading and coronary flow of VDPs and RBPs in a repeatable environment, a physiologic coronary circulation was added to a pre-existing mock circulatory loop. In this study, a physiologic coronary circulation, mimicking a healthy or diseased auto-regulatory response was implemented in a mock circulatory loop. Using the mock circulation loop, a VDP with original (Björk-Shiley) and then replacement (jellyfish) valves was operated in clinically recommended modes and compared to full and partial assist RBP operating at constant speed and rapid speed modulated modes. The Björk-Shiley VDP resulted in increased pressure-volume area, which resulted in greater coronary artery flow when compared to the improved jellyfish valves. Full assist RBP support reduced left ventricular stroke work, pressure-volume area and coronary flow compared to partial assist, whilst the effect of speed modulation modes was not as significant. Of all LVAD operating modes, the counter-pulsed VDP with jellyfish valves demonstrated the greatest reduction in pressure-volume area and improved coronary flow. This study provides a basis for further investigation into RBP speed modulation profiles to match the improved haemodynamic performance of VDPs.

A multi-scale model of the coronary circulation applied to investigate transmural myocardial flow

Distribution of blood flow in myocardium is a key determinant of the localization and severity of myocardial ischemia under impaired coronary perfusion conditions. Previous studies have extensively demonstrated the transmural difference of ischemic vulnerability. However, it remains incompletely understood how transmural myocardial flow is regulated under in vivo conditions. In the present study, a computational model of the coronary circulation was developed to quantitatively evaluate the sensitivity of transmural flow distribution to various cardiovascular and hemodynamic factors. The model was further incorporated with the flow autoregulatory mechanism to simulate the regulation of myocardial flow in the presence of coronary artery stenosis. Numerical tests demonstrated that heart rate (HR), intramyocardial tissue pressure (P_im ), and coronary perfusion pressure (P_per ) were the major determinant factors for transmural flow distribution (evaluated by the subendocardial-to-subepicardial (endo/epi) flow ratio) and that the flow autoregulatory mechanism played an important compensatory role in preserving subendocardial perfusion against reduced P_per . Further analysis for HR variation-induced hemodynamic changes revealed that the rise in endo/epi flow ratio accompanying HR decrease was attributable not only to the prolongation of cardiac diastole relative to systole, but more predominantly to the fall in P_im . Moreover, it was found that P_im and P_per interfered with each other with respect to their influence on transmural flow distribution. These results demonstrate the interactive effects of various cardiovascular and hemodynamic factors on transmural myocardial flow, highlighting the importance of taking into account patient-specific conditions in the explanation of clinical observations.

Blood pressure control and impact on cardiovascular events in patients with type 2 diabetes mellitus: A critical analysis of the literature

High blood pressure in individuals with type2 diabetes mellitus increases the risk of cardiovascular events. The international management guidelines recommend starting pharmacological treatment with blood pressure values >140/90mmHg. However, there is no optimal cut-off point from which cardiovascular events can be reduced without causing adverse events. A blood pressure range of >130/80 to <140/90mmHg seems to be adequate. These values can be achieved through non-pharmacological (diet, exercise) and pharmacological interventions (using drugs that have been shown to reduce cardiovascular events). The choice of one or several drugs must be individualised, according to factors including, ethnicity, age, and associated comorbidities, among others.

Control of Blood Pressure and Cardiovascular Outcomes in Type 2 Diabetes

High blood pressure in patients with diabetes mellitus results in a significant increase in the risk of cardiovascular events and mortality. The current evidence regarding the impact of intervention on blood pressure levels (in accordance with a specific threshold) is not particularly robust. Blood pressure control is more difficult to achieve in patients with diabetes than in non-diabetic patients, and requires using combination therapy in most patients. Different management guidelines recommend initiating pharmacological therapy with values >140/90 mm/Hg; however, an optimal cut point for this population has not been established. Based on the available evidence, it appears that blood pressure targets will probably have to be lower than <140/90mmHg, and that values approaching 130/80mmHg should be recommended. Initial treatment of hypertension in diabetes should include drug classes demonstrated to reduce cardiovascular events; i.e., angiotensin converting-enzyme inhibitors, angiotensin receptor blockers, diuretics, or dihydropyridine calcium channel blockers. The start of therapy must be individualized in accordance with the patient's baseline characteristics, and factors such as associated comorbidities, race, and age, inter alia.

Low diastolic blood pressure and adverse outcomes in heart failure with preserved ejection fraction

BACKGROUND

It remains unknown whether a low diastolic blood pressure (DBP) increases the risks of cardiovascular events and death in patients with heart failure with preserved ejection fraction (HFpEF).

METHODS

We used data from the TOPCAT trial. The primary outcome was a composite of all-cause death, non-fatal myocardial infarction, non-fatal stroke, or hospitalization for heart failure. Hazard ratios (HRs) were analyzed for DBPs of <60, 60-69, 70-79, and ≥90 mm Hg in comparison with a DBP of 80-89 mm Hg using multivariable Cox proportional hazard models.

RESULTS

This study included 3417 patients with HFpEF who had a controlled blood pressure. In the mean follow-up period of 3.0 years, 881 patients experienced at least one confirmed primary outcome event. Compared with patients with a DBP of 80-89 mm Hg, the adjusted HRs for primary outcome events were significantly higher in those with DBPs of <60 mm Hg (HR: 2.19 [95% confidence interval,1.72-2.78]) and 60-69 mm Hg (HR: 1.52 [1.23-1.87]). Similarly, the adjusted HRs for all-cause death, major cardiovascular events, and hospitalization for heart failure, but not stroke, were significantly higher in patients with a DBP of <70 mm Hg. A relationship between a low DBP and adverse outcomes was found in HFpEF patients with a systolic blood pressure of ≥120 mm Hg; however, a low systolic blood pressure with a DBP of ≥70 mm Hg was not associated with these event risks.

CONCLUSIONS

A low DBP increased the risks of adverse outcomes in patients with HFpEF.

The J-shaped Curve for Blood Pressure and Cardiovascular Disease Risk: Historical Context and Recent Updates

PURPOSE OF REVIEW

The definition and treatment of hypertension have both changed dramatically over the last century, with recent trials suggesting benefit for lower blood pressure (BP) targets than ever before considered. However, tempering the enthusiasm for more intensive BP targets are long-held concerns that BP reduction below a certain threshold may pose dangers, the so-called "J-curve." In this review, we summarize the evidence for a J-curve in the treatment of hypertension.

RECENT FINDINGS

The Systolic Blood Pressure Intervention Trial (SPRINT) reported that achieving a systolic BP target of 120 mmHg reduces cardiovascular disease in high-risk individuals, supporting more intensive BP reduction. However, contemporary observational studies consistently demonstrate a BP J-curve, the threshold of which is often close to the SPRINT target. Studies also suggest that the BP level of this J-curve may vary based on patient characteristics, including age and comorbidities. There is also more compelling evidence for the specific presence of a J-curve between diastolic BP and coronary events, in contrast to conflicting evidence of a J-curve with systolic BP and cardiovascular disease more generally. There is increased risk of coronary events below a diastolic BP of 60-70 mmHg. In comparison, the presence of a systolic J-curve is less clear and some persons at high risk may actually benefit from systolic levels down to 120 mmHg. Therefore, we suggest a personalized approach to BP management considering individual risks, benefits, and preferences when choosing therapeutic targets. Further, well-designed studies are required to support our suggestions and to define J-curve thresholds more clearly.

Aggressive systolic blood pressure control in older subjects: benefits and risks

Systolic hypertension, especially isolated systolic hypertension (ISH) is very common in older subjects aged ≥ 65 years and is a major risk factor for cardiovascular disease (CVD), strokes, heart failure (HF) and chronic kidney disease (CKD). It is also, directly and linearly related with these complications irrespective of sex, or ethnicity, but it is worse with the advancement of age. Effective control of systolic blood pressure (SBP), is associated with significant reduction in the incidence of these complications. Currently, there is a debate about the optimal SBP control in view of the Systolic Blood Pressure Intervention Trial (SPRINT) showing beneficial cardiovascular (CV) effects of intensive SBP of < 120 mmHg in older patients. Also, the recently released blood pressure (BP) guidelines by the American College of Cardiology, the American Heart Association and the American Society of Hypertension (ACC/AHA/ASH) recommend a SBP reduction of < 130 mmHg. These SBP treatment recommendations are in contrast with the current (JNC VIII) committee of BP treatment guidelines, which recommend a SBP reduction < 150 mmHg for the same age of patients. All these different recommendations have created a debate regarding the optimal treatment targets for the systolic hypertension of the elderly patients. To gain more information a focused Medline search was conducted from 2010 to 2017 using the terms, systolic blood pressure, aggressive control, older subjects, treatment guidelines, and 37 pertinent papers were retrieved. The findings from these studies suggest a SBP reduction of < 140 mm Hg for persons aged ≥ 60 years, with an attempt for SBP reduction to ≤130 mm Hg in healthier subjects and hose with CVD, DM, and CKD. Care should be taken not to further reduce the SBP in older subjects if their DBP is ≤60 mmHg for the fear of J-curve effect.

The impact of tissue Doppler index E/e' ratio on instantaneous wave-free ratio

BACKGROUND

The instantaneous wave-free ratio (iFR) is a vasodilator-free, invasive pressure wire index of the functional severity of coronary stenosis and is calculated under resting conditions. In a recent study, iFR was found to be more closely linked to coronary flow reserve (CFR) than fractional flow reserve (FFR). E/e' is a surrogate marker of left ventricular (LV) filling pressure and LV diastolic dysfunction. Coronary resting flow was found to be increased in patients with elevated E/e', and higher coronary resting flow was associated with lower CFR. Higher baseline coronary flow induces a greater loss of translesional pressure and may affect iFR. However, no reports have examined the impact of E/e' on iFR. The purpose of this study was to assess the relationship between iFR and E/e' compared with FFR.

METHODS AND RESULTS

We retrospectively examined 103 consecutive patients (142 with stenosis) whose iFR, FFR, and E/e' were measured simultaneously. The mean age, LV mass index, and systolic blood pressure of patients with elevated E/e' were higher than those of patients with normal E/e'. Although no significant differences were observed in mean FFR values and % diameter stenosis, the mean iFR value in patients with elevated E/e' was significantly lower than that in patients with normal E/e'. The iFR was negatively correlated with E/e', while there was no correlation between FFR and E/e'. Multivariate analysis showed that E/e' and % diameter stenosis were independent determinants of iFR.

CONCLUSION

E/e' ratio affects iFR values. Our results suggest that FFR mainly reflects the functional severity of the epicardial stenosis whereas iFR could potentially be influenced by not only epicardial stenosis but also other factors related to LV filling pressure or LV diastolic dysfunction. Further research is needed to understand the underlying mechanisms that influence the evaluation of iFR in patients with elevated E/e'.

Left Ventricular Geometry Determines Prognosis and Reverse J-Shaped Relation Between Blood Pressure and Mortality in Ischemic Stroke Patients

OBJECTIVES

This study sought to investigate the prognostic significance of left ventricular (LV) mass and geometry in ischemic stroke survivors, as well as the LV geometry-specific differences in the blood pressure-mortality relationship.

BACKGROUND

LV mass and geometry are well-known prognostic factors in various populations; however, there are no data on their role in ischemic stroke patients.

METHODS

We prospectively recruited 2,328 consecutive patients admitted with acute ischemic stroke to our institute between 2002 and 2010. Of these, 2,069 patients were analyzed in whom echocardiographic data were available to assess LV mass and geometry.

RESULTS

All-cause mortality was significantly greater in patients with concentric hypertrophy (adjusted hazard ratio [HR]: 1.417; 95% confidence interval [CI]: 1.045 to 1.920) and concentric remodeling (HR: 1.540; 95% CI: 1.115 to 2.127) but nonsignificantly in those with eccentric hypertrophy (HR: 1.388; 95% CI: 0.996 to 1.935) compared with normal geometry in multivariate analyses. Relative wall thickness was a significant predictor of all-cause mortality (HR: 1.149 per 0.1-U increase in relative wall thickness; 95% CI: 1.021 to 1.307), whereas LV mass index was not (HR: 1.003 per 1 g/m² increase in LV mass index; 95% CI: 0.999 to 1.007). Similar results were observed with cardiovascular mortality. In multivariable fractional polynomials, patients with altered LV geometry showed reverse J-curve relationships between acute-phase systolic blood pressure and all-cause or cardiovascular mortality, with the highest risks in the lower extremes, whereas those with normal geometry did not.

CONCLUSIONS

Echocardiographic assessment of LV geometry provided independent and additive prognostic information in ischemic stroke patients. A reverse J-shaped relation of mortality with blood pressure was found in patients with abnormal LV geometry.

Hypertension and coronary artery disease: epidemiology, physiology, effects of treatment, and recommendations : A joint scientific statement from the Austrian Society of Cardiology and the Austrian Society of Hypertension

High blood pressure is a major modifiable risk factor for all clinical manifestations of coronary artery disease (CAD). In people without known cardiovascular disease, the lowest systolic (down to 90-114 mmHg) and the lowest diastolic (down to 60-74 mmHg) pressures are associated with the lowest risk for developing CAD. Although diastolic blood pressure is the strongest predictor of CAD in younger and middle-aged people, this relationship becomes inverted and pulse pressure shows the strongest direct relationship with CAD in people above 60 years of age.Pathophysiological mechanisms of blood pressure as a risk factor for CAD are complex and include the influence of blood pressure as a physical force on the development of the atherosclerotic plaque, and the relationship between pulsatile hemodynamics/arterial stiffness and coronary perfusion. Treatment of arterial hypertension has been proven to prevent coronary events in patients without clinical CAD. In patients with established CAD, the effect of blood pressure lowering per se is beneficial, probably more than specific drugs or drug classes. The important exceptions are beta blockers (BBs), which are superior to all other drug classes for use after a recent myocardial infarction. Blood pressure targets in patients with established CAD have created controversy in the light of the so-called J-curve phenomenon, which describes an increase in coronary events at lower diastolic blood pressures. One explanation for this observation is that perfusion of the left ventricle occurs predominantly during diastole, and that coronary autoregulation may be exhausted with low diastolic blood pressure in the setting of left ventricular hypertrophy and atherosclerotic narrowing of the epicardial coronaries. The worst situation is a high systolic blood pressure in the presence of a low diastolic blood pressure, both a hallmark of increased aortic stiffness. However, the lowering of systolic blood pressure is clearly beneficial in this setting, even at the price of further lowering diastolic pressure. Primary blood pressure goal in patients with established CAD is below 140/90 mmHg. Recent studies suggest that a lower systolic blood pressure may be appropriate, whereas caution is advised with diastolic blood pressure below 60 mmHg.

The ideal blood pressure target to prevent cardiovascular disease in type 2 diabetes: a neutral viewpoint

Type 2 diabetes mellitus (T2DM) and essential hypertension are often associated, and retrospective data analyses suggest an association between lower blood pressure (BP) values and lower cardiovascular (CV) risk in patients with T2DM. However, the most recent intervention trials fail to demonstrate a further CV risk reduction, for BP levels <130/80 mm Hg, when compared to levels <140/90 mm Hg. Moreover, a J-shaped, rather than a linear, relationship of BP reduction with incident CV events has been strongly suggested. We here debate the main available evidences for and against the concept of 'the lower the better', in the light of the main intervention trials and meta-analyses, with a particular emphasis on the targets to be pursued in elderly patients. Finally, the most recent guidelines of the scientific societies are critically discussed.

Prevention of cardiovascular disease guided by total risk estimations--challenges and opportunities for practical implementation: highlights of a CardioVascular Clinical Trialists (CVCT) Workshop of the ESC Working Group on CardioVascular Pharmacology and Drug Therapy

This paper presents a summary of the potential practical and economic barriers to implementation of primary prevention of cardiovascular disease guided by total cardiovascular risk estimations in the general population. It also reviews various possible solutions to overcome these barriers. The report is based on discussion among experts in the area at a special CardioVascular Clinical Trialists workshop organized by the European Society of Cardiology Working Group on Cardiovascular Pharmacology and Drug Therapy that took place in September 2009. It includes a review of the evidence in favour of the ‘treat-to-target’ paradigm, as well as potential difficulties with this approach, including the multiple pathological processes present in high-risk patients that may not be adequately addressed by this strategy. The risk-guided therapy approach requires careful definitions of cardiovascular risk and consideration of clinical endpoints as well as the differences between trial and ‘real-world’ populations. Cost-effectiveness presents another issue in scenarios of finite healthcare resources, as does the difficulty of documenting guideline uptake and effectiveness in the primary care setting, where early modification of risk factors may be more beneficial than later attempts to manage established disease. The key to guideline implementation is to improve the quality of risk assessment and demonstrate the association between risk factors, intervention, and reduced event rates. In the future, this may be made possible by means of automated data entry and various other measures. In conclusion, opportunities exist to increase guideline implementation in the primary care setting, with potential benefits for both the general population and healthcare resources.

Myocardial perfusion and the J curve association between diastolic blood pressure and mortality

BACKGROUND

The J-curve relationship between brachial diastolic blood pressure (DBP) and mortality is believed to be mediated through reduced myocardial perfusion. This study aimed to determine the relationship between DBP and subendocardial perfusion in patients with and without coronary artery disease (CAD) and to examine central hemodynamic variables that may explain the risk associated with low DBP (aortic stiffness, central pulse pressure, and augmentation index).

METHODS

Brachial DBP and radial tonometry were measured in 134 patients with CAD (aged 76±7years; 69% male), 134 individuals without a prior cardiovascular event (control subjects) (aged 77±2years; 69% male) and 47 patients (aged 63±10years) during dobutamine stress echocardiography. Central hemodynamics and subendocardial viability ratio (SEVR), a marker of subendocardial perfusion, were recorded by tonometry.

RESULTS

There was no difference in DBP or SEVR between control subjects and CAD patients (P > 0.05), nor was there a difference in SEVR across quartiles of DBP in CAD patients (P = 0.07) or control subjects (P = 0.14). After adjustment for age and height, associations between DBP and SEVR in control subjects (r = 0.185; P = 0.03) and CAD patients (r = 0.204; P = 0.02) were attenuated (P = 0.07 and P = 0.11, respectively). There were no significant relationships between DBP and central hemodynamics (P > 0.05 for all). At peak dobutamine stress, SEVR was significantly reduced in patients with inducible ischemia vs. those with nonischemic response (84±17 vs. 101±22%; P = 0.01). However, DBP was not significantly different (65±14 vs. 67±15mm Hg; P = 0.32).

CONCLUSIONS

Brachial DBP is a poor marker of subendocardial perfusion. The J-curve relationship between DBP and mortality is unlikely attributable to reduced myocardial perfusion or adverse central hemodynamics.

Low Diastolic Blood Pressure as a Risk for All-Cause Mortality in VA Patients

Background. A paradoxical increase in cardiovascular events has been reported with intensively lowering diastolic blood pressure (DBP). This J-curve phenomenon has challenged the aggressive lowering of blood pressure, especially in patients with coronary artery disease. Objective. Our objective was to study the effects of low DBP on mortality and determine a threshold for which DBP should not be lowered beyond. Methods. We evaluated a two-year cross-section of primary care veteran patients, from 45 to 85 years of age. Receiver operating characteristics (ROC) were employed to establish an optimal cut-off point for DBP. Propensity-score matching and multivariate logistic regression were used to control for confounders. All-cause mortality was the primary outcome. Results. 14,270 patients were studied. An ROC curve found a threshold value of DBP 70 mmHg had the greatest association with mortality (P < 0.001). 49% of patients had a DBP of 70 mmHg or less. Using a propensity-matched multivariate logistic regression, odds ratio for all-cause mortality in subjects with a DBP less than 70 mmHg was 1.5 (95% CI 1.3-1.8). Conclusions. Reduction of DBP below 70 mmHg is associated with increased all-cause mortality. Hypertension guidelines should include a minimum blood pressure target.

Blood pressure j-curve: current concepts

The blood pressure (BP) J-curve debate started in 1979, and we still cannot definitively answer all the questions. However, available studies of antihypertensive treatment provide strong evidence for J-shaped relationships between both diastolic and systolic BP and main outcomes in the general population of hypertensive patients, as well as in high-risk populations, including subjects with coronary artery disease, diabetes mellitus, left ventricular hypertrophy, and elderly patients. However, further studies are still necessary in order to clarify this issue. This is connected to the fact that most available studies were observational, and randomized trials did not have or lost their statistical power and were inconclusive. Perhaps only the Systolic Blood Pressure Intervention Trial (SPRINT) and Optimal Blood Pressure and Cholesterol Targets for Preventing Recurrent Stroke in Hypertensives (ESH-CHL-SHOT) will be able to finally answer all the questions. According to the current state of knowledge, it seems reasonable to suggest lowering BP to values within the 130-139/80-85 mmHg range, possibly close to the lower values in this range, in all hypertensive patients and to be very careful with further BP level reductions, especially in high-risk hypertensive patients.

The J-curve revisited: a therapeutic dilemma

The J-curve in hypertension treatment refers to the relationship between achieved diastolic blood pressure (BP) and cardiovascular morbidity and mortality, specifically related to coronary heart disease (CHD). As diastolic BP decreases below a certain threshold or nadir, the risk of cardiovascular events increases. This phenomenon was first described over 30 years ago and its significance has been debated ever since. We review in detail the literature for and against the existence of this J-curve and discuss its purported pathophysiology. Most notably, recent post hoc analyses of large contemporary randomized trials in patients with documented CHD strongly support its existence. Given the current emphasis on strict BP control, especially in high-risk patients like those with CHD, diabetes, and chronic kidney disease, we discuss the implications this J-curve may have for treating hypertension in the individual patient.

J Curve in Hypertension

The relationship between blood pressure and cardiovascular disease risk among treated hypertensives is J-shaped: risk is increased at high levels of blood pressure, falls in parallel with blood pressure reduction and increases again when blood pressure falls below a nadir (the point at which blood pressure is too low to maintain perfusion of vital organs). Randomized controlled trials of antihypertensive treatment have identified J-shaped relationships between achieved systolic and diastolic blood pressures and all-cause mortality, as well as fatal and nonfatal cardiovascular events, but not stroke or renal outcomes, in the general population of hypertensives and high-risk prehypertensives, particularly in subgroups such as the elderly and those with coronary artery disease, chronic kidney disease, diabetes, left ventricular hypertrophy, and high cardiovascular risk because of multiple comorbidities and concomitant risk factors. Blood pressure targets <130-140/70-85 mm Hg were not beneficial for any outcome except stroke and chronic kidney disease.

Association of abnormal coronary microcirculatory function with impaired response of longitudinal left ventricular function during adenosine stress echocardiography in untreated hypertensive patients

AIMS

Coronary microcirculation is disturbed in hypertensive patients. We investigated the association of coronary flow reserve (CFR) with the response of left ventricular (LV) function as assessed by tissue Doppler imaging (TDI) during adenosine stress echocardiography in never-treated hypertensive patients.

METHODS AND RESULTS

We studied 90 hypertensive patients and 30 control subjects, matched for age and sex, by adenosine stress echocardiography. We measured: (i) CFR, E and A Doppler, S', E', A' mitral annulus velocities with TDI, as well as the E'/A' ratio and the E/E' ratio before and during adenosine infusion (ii) the %changes of the measured indices between baseline and adenosine infusion. After adenosine infusion, there was an increase in S', E', and A' in all patients and controls (P < 0.05). Compared with controls and patients with CFR ≥ 2.5, patients with CFR <2.5 showed a smaller increase in S' (28.6 vs. 30.0 vs. 11.1%, F for interaction = 14.592) and E' (33.3 vs. 33.3 vs.1.5%, F = 28.927) as well as a decrease in E'/A' (9.2 vs. 6.4% vs. -20.0%, F = 5.128) and an increase in E/E' (-6.1 vs. -1.6 vs. 30.5%. F = 12.780) after adenosine infusion (P < 0.05 for all comparisons). CFR was independently related to %changes of TDI parameters (regression coefficient b = 0.576 for S'; b = 0.517 for E'; b = 0.473 for E'/A'; b = -0.520 for E/E', respectively, P < 0.001). By the receiver operating curve, a CFR <2.5 predicted the median changes of all measured TDI markers, with a sensitivity and specificity over 70% (AUC >75%, P < 0.05).

CONCLUSION

An abnormal response of the LV longitudinal function during adenosine stress echocardiography is related to impaired CFR in untreated hypertensive patients.

Tight blood pressure control in diabetes: evidence-based review of treatment targets in patients with diabetes

Blood pressure (BP) targets in diabetic patients stills represent the object of a major debate, fueled by the recent publication of post hoc observational analyses of the INVEST and the ONTARGET trials, suggesting an increased risk of cardiovascular events with tighter control, the J-curve effect, and by the results of the ACCORD trial, showing no improvements in the composite primary outcome of nonfatal myocardial infarction, stroke, or cardiovascular death in the intensive BP-lowering arm (<120/80 mmHg). In the present review, we focus on existing evidence about different BP targets in diabetic subjects and we present the results of our recent meta-analysis, showing that tight BP control may significantly reduce the risk of stroke in these patients without increasing the risk of myocardial infarction. Therapeutic inertia (leaving diabetic patients with BP values of 140/90 mmHg or higher) should be avoided at all costs, as this would lead to an unacceptable toll in terms of human lives, suffering, and socioeconomic costs.

Safety and efficacy of low blood pressures among patients with diabetes: subgroup analyses from the ONTARGET (ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial)

OBJECTIVES

We sought to determine whether the blood pressure (BP) levels at which cardiovascular (CV) protection is achieved differ between diabetic and nondiabetic patients from the ONTARGET (ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial).

BACKGROUND

Greater absolute benefits of BP reductions have been claimed for diabetic as compared with nondiabetic patients.

METHODS

A total of 25,584 patients (9,603 diabetic), older than 55 years, at high CV risk were randomized to ramipril, telmisartan, or both and observed for 4.6 years. We pooled the treatment arms to examine the relationships between BP and the primary composite outcome (CV death, nonfatal myocardial infarction or stroke, or hospitalized heart failure) and its components.

RESULTS

The primary outcome occurred in 1,938 (20.2%) diabetic patients and in 2,276 (14.2%) nondiabetic patients. Compared with nondiabetic patients, diabetic patients had a significantly higher risk for the primary endpoint (hazard ratio [HR]: 1.48; 95% confidence interval [CI]: 1.38 to 1.57) and CV death (HR: 1.56; 95% CI: 1.42 to 1.71); myocardial infarction (HR: 1.30 (95% CI: 1.17 to 1.46); stroke (HR: 1.39; 95% CI: 1.23 to 1.56); and congestive heart failure hospitalization (HR: 2.06; 95% CI: 1.82 to 2.32). The CV risk was significantly higher in diabetic than in nondiabetic patients regardless of the systolic BP changes during treatment. In both diabetic and nondiabetic patients, progressively greater systolic BP reductions were accompanied by reduced risk for the primary outcome only if baseline systolic BP levels ranged from 143 to 155 mm Hg; except for stroke, there was no benefit in fatal or nonfatal CV outcomes by reducing systolic BP below 130 mm Hg.

CONCLUSIONS

The relationship between BP and overall CV risk had a similar pattern in diabetic and nondiabetic patients over a wide range of baseline and in-treatment BP values although, for the same systolic BP, a higher risk is observed in diabetic patients.

The significance of the j-curve in hypertension and coronary artery diseases

The J-curve effect describes an inverse relation between low blood pressure (BP) and cardiovascular complications. This effect is more pronounced in patients with preexisting coronary artery disease (CAD), hypertension or left ventricular hypertrophy (LVH). The recent large clinical outcomes trials have observed a J-curve effect between a diastolic BP of 70-80 mmHg as well as a systolic BP <130 mmHg. The J-curve phenomenon does not appear in stroke or renal disease. This is because the coronary arteries are perfused during diastole, but the cerebral and renal perfusion mainly occurs in systole. Therefore, caution should be taken to maintain the diastolic blood pressure (DBP) at minimum of 70 mmHg and possibly to maintain the DBP between 80-85 mmHg in patients with severe LVH, CAD or vascular diseases. BP control in high-risk elderly patients should be carefully done as undergoing aggressive therapy to lower the systolic blood pressure below 140 mmHg can cause cardiovascular complications due to the severely reduced DBP and increased pulse pressure.

Current status of aggressive blood pressure control

The concept of treatment of hypertension has gone through wide swings over the years. From ignoring blood pressure (BP) treatment initially, to aggressive BP control recently. As newer and more effective drugs were developed, it was possible to lower BP to very low levels. However, recent studies have shown that aggressive BP control might not be in the best interest of the patient. Low levels of diastolic BP (DBP) have been associated with increased cardiovascular events, a situation known as the J-curve effect. This has been seen mostly with low DBP, since the coronary arteries are perfused during the diastolic phase of the cardiac cycle. Due to an autoregulatory mechanism, the heart is protected against wide fluctuations of BP. However, the presence of coronary heart disease, hypertension, especially with left ventricular hypertrophy, shift the curve to higher BP levels and makes the heart more liable to DBP fluctuations. The J-Curve effect has been reported by most investigators, but not by others. Recently, a J-Curve effect has been observed with systolic BP (SBP), as well. In contrast to the heart, the brain is very infrequently subjected to J-curve effect, and in contrast to the heart, the brain's blood flow autoregulation depends mostly on the SBP. A Medline search of the English literature on this subject was conducted between 1992 and 2010 and 11 pertinent articles were selected. These articles with collateral literature will be discussed in this concise review.