Heart rate variability: standards of measurement, physiological interpretation and clinical use. Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology.

ABCD
: Appropriate Blood pressure Control in Diabetes
ABI
: ankle–brachial index
ABPM
: ambulatory blood pressure monitoring
ACCESS
: Acute Candesartan Cilexetil Therapy in Stroke Survival
ACCOMPLISH
: Avoiding Cardiovascular Events in Combination Therapy in Patients Living with Systolic Hypertension
ACCORD
: Action to Control Cardiovascular Risk in Diabetes
ACE
: angiotensin-converting enzyme
ACTIVE I
: Atrial Fibrillation Clopidogrel Trial with Irbesartan for Prevention of Vascular Events
ADVANCE
: Action in Diabetes and Vascular Disease: Preterax and Diamicron-MR Controlled Evaluation
AHEAD
: Action for HEAlth in Diabetes
ALLHAT
: Antihypertensive and Lipid-Lowering Treatment to Prevent Heart ATtack
ALTITUDE
: ALiskiren Trial In Type 2 Diabetes Using Cardio-renal Endpoints
ANTIPAF
: ANgioTensin II Antagonist In Paroxysmal Atrial Fibrillation
APOLLO
: A Randomized Controlled Trial of Aliskiren in the Prevention of Major Cardiovascular Events in Elderly People
ARB
: angiotensin receptor blocker
ARIC
: Atherosclerosis Risk In Communities
ARR
: aldosterone renin ratio
ASCOT
: Anglo-Scandinavian Cardiac Outcomes Trial
ASCOT-LLA
: Anglo-Scandinavian Cardiac Outcomes Trial—Lipid Lowering Arm
ASTRAL
: Angioplasty and STenting for Renal Artery Lesions
A-V
: atrioventricular
BB
: beta-blocker
BMI
: body mass index
BP
: blood pressure
BSA
: body surface area
CA
: calcium antagonist
CABG
: coronary artery bypass graft
CAPPP
: CAPtopril Prevention Project
CAPRAF
: CAndesartan in the Prevention of Relapsing Atrial Fibrillation
CHD
: coronary heart disease
CHHIPS
: Controlling Hypertension and Hypertension Immediately Post-Stroke
CKD
: chronic kidney disease
CKD-EPI
: Chronic Kidney Disease—EPIdemiology collaboration
CONVINCE
: Controlled ONset Verapamil INvestigation of CV Endpoints
CT
: computed tomography
CV
: cardiovascular
CVD
: cardiovascular disease
D
: diuretic
DASH
: Dietary Approaches to Stop Hypertension
DBP
: diastolic blood pressure
DCCT
: Diabetes Control and Complications Study
DIRECT
: DIabetic REtinopathy Candesartan Trials
DM
: diabetes mellitus
DPP-4
: dipeptidyl peptidase 4
EAS
: European Atherosclerosis Society
EASD
: European Association for the Study of Diabetes
ECG
: electrocardiogram
EF
: ejection fraction
eGFR
: estimated glomerular filtration rate
ELSA
: European Lacidipine Study on Atherosclerosis
ESC
: European Society of Cardiology
ESH
: European Society of Hypertension
ESRD
: end-stage renal disease
EXPLOR
: Amlodipine–Valsartan Combination Decreases Central Systolic Blood Pressure more Effectively than the Amlodipine–Atenolol Combination
FDA
: U.S. Food and Drug Administration
FEVER
: Felodipine EVent Reduction study
GISSI-AF
: Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico-Atrial Fibrillation
HbA1c
: glycated haemoglobin
HBPM
: home blood pressure monitoring
HOPE
: Heart Outcomes Prevention Evaluation
HOT
: Hypertension Optimal Treatment
HRT
: hormone replacement therapy
HT
: hypertension
HYVET
: HYpertension in the Very Elderly Trial
IMT
: intima-media thickness
I-PRESERVE
: Irbesartan in Heart Failure with Preserved Systolic Function
INTERHEART
: Effect of Potentially Modifiable Risk Factors associated with Myocardial Infarction in 52 Countries
INVEST
: INternational VErapamil SR/T Trandolapril
ISH
: Isolated systolic hypertension
JNC
: Joint National Committee
JUPITER
: Justification for the Use of Statins in Primary Prevention: an Intervention Trial Evaluating Rosuvastatin
LAVi
: left atrial volume index
LIFE
: Losartan Intervention For Endpoint Reduction in Hypertensives
LV
: left ventricle/left ventricular
LVH
: left ventricular hypertrophy
LVM
: left ventricular mass
MDRD
: Modification of Diet in Renal Disease
MRFIT
: Multiple Risk Factor Intervention Trial
MRI
: magnetic resonance imaging
NORDIL
: The Nordic Diltiazem Intervention study
OC
: oral contraceptive
OD
: organ damage
ONTARGET
: ONgoing Telmisartan Alone and in Combination with Ramipril Global Endpoint Trial
PAD
: peripheral artery disease
PATHS
: Prevention And Treatment of Hypertension Study
PCI
: percutaneous coronary intervention
PPAR
: peroxisome proliferator-activated receptor
PREVEND
: Prevention of REnal and Vascular ENdstage Disease
PROFESS
: Prevention Regimen for Effectively Avoiding Secondary Strokes
PROGRESS
: Perindopril Protection Against Recurrent Stroke Study
PWV
: pulse wave velocity
QALY
: Quality adjusted life years
RAA
: renin-angiotensin-aldosterone
RAS
: renin-angiotensin system
RCT
: randomized controlled trials
RF
: risk factor
ROADMAP
: Randomized Olmesartan And Diabetes MicroAlbuminuria Prevention
SBP
: systolic blood pressure
SCAST
: Angiotensin-Receptor Blocker Candesartan for Treatment of Acute STroke
SCOPE
: Study on COgnition and Prognosis in the Elderly
SCORE
: Systematic COronary Risk Evaluation
SHEP
: Systolic Hypertension in the Elderly Program
STOP
: Swedish Trials in Old Patients with Hypertension
STOP-2
: The second Swedish Trial in Old Patients with Hypertension
SYSTCHINA
: SYSTolic Hypertension in the Elderly: Chinese trial
SYSTEUR
: SYSTolic Hypertension in Europe
TIA
: transient ischaemic attack
TOHP
: Trials Of Hypertension Prevention
TRANSCEND
: Telmisartan Randomised AssessmeNt Study in ACE iNtolerant subjects with cardiovascular Disease
UKPDS
: United Kingdom Prospective Diabetes Study
VADT
: Veterans' Affairs Diabetes Trial
VALUE
: Valsartan Antihypertensive Long-term Use Evaluation
WHO
: World Health Organization

### 1.1 Principles

The 2013 guidelines on hypertension of the European Society of Hypertension (ESH) and the European Society of Cardiology …

/pdf/2013-esh-esc-guidelines-for-the-management-of-arterial-4ydvs5ifsx.pdf

2013 ESH/ESC Guidelines for the management of arterial hypertension: The Task Force for the management of arterial hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC).

2007 Guidelines for the Management of Arterial Hypertension : The Task Force for the Management of Arterial Hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC).

ABI
: ankle–brachial index
ACCORD
: Action to Control Cardiovascular Risk in Diabetes
ADVANCE
: Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation
AGREE
: Appraisal of Guidelines Research and Evaluation
AHA
: American Heart Association
apoA1
: apolipoprotein A1
apoB
: apolipoprotein B
CABG
: coronary artery bypass graft surgery
CARDS
: Collaborative AtoRvastatin Diabetes Study
CCNAP
: Council on Cardiovascular Nursing and Allied Professions
CHARISMA
: Clopidogrel for High Athero-thrombotic Risk and Ischemic Stabilisation, Management, and Avoidance
CHD
: coronary heart disease
CKD
: chronic kidney disease
COMMIT
: Clopidogrel and Metoprolol in Myocardial Infarction Trial
CRP
: C-reactive protein
CURE
: Clopidogrel in Unstable Angina to Prevent Recurrent Events
CVD
: cardiovascular disease
DALYs
: disability-adjusted life years
DBP
: diastolic blood pressure
DCCT
: Diabetes Control and Complications Trial
ED
: erectile dysfunction
eGFR
: estimated glomerular filtration rate
EHN
: European Heart Network
EPIC
: European Prospective Investigation into Cancer and Nutrition
EUROASPIRE
: European Action on Secondary and Primary Prevention through Intervention to Reduce Events
GFR
: glomerular filtration rate
GOSPEL
: Global Secondary Prevention Strategies to Limit Event Recurrence After MI
GRADE
: Grading of Recommendations Assessment, Development and Evaluation
HbA1c
: glycated haemoglobin
HDL
: high-density lipoprotein
HF-ACTION
: Heart Failure and A Controlled Trial Investigating Outcomes of Exercise TraiNing
HOT
: Hypertension Optimal Treatment Study
HPS
: Heart Protection Study
HR
: hazard ratio
hsCRP
: high-sensitivity C-reactive protein
HYVET
: Hypertension in the Very Elderly Trial
ICD
: International Classification of Diseases
IMT
: intima-media thickness
INVEST
: International Verapamil SR/Trandolapril
JTF
: Joint Task Force
LDL
: low-density lipoprotein
Lp(a)
: lipoprotein(a)
LpPLA2
: lipoprotein-associated phospholipase 2
LVH
: left ventricular hypertrophy
MATCH
: Management of Atherothrombosis with Clopidogrel in High-risk Patients with Recent Transient Ischaemic Attack or Ischaemic Stroke
MDRD
: Modification of Diet in Renal Disease
MET
: metabolic equivalent
MONICA
: Multinational MONItoring of trends and determinants in CArdiovascular disease
NICE
: National Institute of Health and Clinical Excellence
NRT
: nicotine replacement therapy
NSTEMI
: non-ST elevation myocardial infarction
ONTARGET
: Ongoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial
OSA
: obstructive sleep apnoea
PAD
: peripheral artery disease
PCI
: percutaneous coronary intervention
PROactive
: Prospective Pioglitazone Clinical Trial in Macrovascular Events
PWV
: pulse wave velocity
QOF
: Quality and Outcomes Framework
RCT
: randomized clinical trial
RR
: relative risk
SBP
: systolic blood pressure
SCORE
: Systematic Coronary Risk Evaluation Project
SEARCH
: Study of the Effectiveness of Additional Reductions in Cholesterol and
SHEP
: Systolic Hypertension in the Elderly Program
STEMI
: ST-elevation myocardial infarction
SU.FOL.OM3
: SUpplementation with FOlate, vitamin B6 and B12 and/or OMega-3 fatty acids
Syst-Eur
: Systolic Hypertension in Europe
TNT
: Treating to New Targets
UKPDS
: United Kingdom Prospective Diabetes Study
VADT
: Veterans Affairs Diabetes Trial
VALUE
: Valsartan Antihypertensive Long-term Use
VITATOPS
: VITAmins TO Prevent Stroke
VLDL
: very low-density lipoprotein
WHO
: World Health Organization

### 1.1 Introduction

Atherosclerotic cardiovascular disease (CVD) is a chronic disorder developing insidiously throughout life and usually progressing to an advanced stage by the time symptoms occur. It remains the major cause of premature death in Europe, even though CVD mortality has …

/pdf/european-guidelines-on-cardiovascular-disease-prevention-in-4z4nw4311i.pdf

European Guidelines on Cardiovascular Disease Prevention in Clinical Practice (Version 2012)

Because of new evidence on several diagnostic and therapeutic aspects of hypertension, the present guidelines differ in many respects from the previous ones. Some of the most important differences are listed below: 
1. Epidemiological data on hypertension and BP control in Europe. 
2. Strengthening of the prognostic value of home blood pressure monitoring (HBPM) and of its role for diagnosis and management of hypertension, next to ambulatory blood pressure monitoring (ABPM). 
3. Update of the prognostic significance of night-time BP, white-coat hypertension and masked hypertension. 
4. Re-emphasis on integration of BP, cardiovascular (CV) risk factors, asymptomatic organ damage (OD) and clinical complications for total CV risk assessment. 
5. Update of the prognostic significance of asymptomatic OD, including heart, blood vessels, kidney, eye and brain. 
6. Reconsideration of the risk of overweight and target body mass index (BMI) in hypertension. 
7. Hypertension in young people. 
8. Initiation of antihypertensive treatment. More evidence-based criteria and no drug treatment of high normal BP. 
9. Target BP for treatment. More evidence-based criteria and unified target systolic blood pressure (SBP) (<140 mmHg) in both higher and lower CV risk patients. 
10. Liberal approach to initial monotherapy, without any all-ranking purpose. 
11. Revised schema for priorital two-drug combinations. 
12. New therapeutic algorithms for achieving target BP. 
13. Extended section on therapeutic strategies in special conditions. 
14. Revised recommendations on treatment of hypertension in the elderly. 
15. Drug treatment of octogenarians. 
16. Special attention to resistant hypertension and new treatment approaches. 
17. Increased attention to OD-guided therapy. 
18. New approaches to chronic management of hypertensive disease

/pdf/2013-esh-esc-guidelines-for-the-management-of-arterial-4eubk4p0u3.pdf

2013 ESH/ESC Guidelines for the management of arterial hypertension: the Task Force for the management of arterial hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC)

Subthreshold stimulation without capture reduces the stimulation threshold and changes the action potential of subsequent suprathreshold stimulation, a phenomenon known as Wedensky modulation (WM). Patients with ventricular tachycardia (VT) inducible during electrophysiological testing (n = 47, mean age 63 +/- 13 years, 83% men), and healthy controls (n = 30, mean age 44 +/- 16 years, 60% men) were subjected to transthoracic external subthreshold stimulation between surface precordial and left subscapular patch electrodes. Stimuli of 5, 10, 20, and 40 mA were delivered for 2 ms, in synchrony with, or 20 ms after, R wave detection. A total of 60-200 subthreshold stimulated QRS complexes were averaged and compared with averaged nonstimulated complexes recorded during the same experimental session. To detect transient changes within the QRS complex, both signals were decomposed with 54 scales of Morlet analyzing wavelets (central frequencies 40-250 Hz). Wavelet vector magnitude was obtained for stimulated and nonstimulated complexes. Their difference created a wavelet residuum (WR) that characterized WM numerically. The surface area of the three-dimensional envelope of WR was measured and statistically compared between VT patients and healthy controls. WR showed a significantly greater increase in the spectral power of the stimulated complex in healthy controls than in VT patients (P < 0.01). In conclusion, (1) wavelet decomposition is a suitable tool to analyze WM, (2) WM in the late QRS complex is short, and (3) VT patients are less sensitive to WM, particularly at low subthreshold energies.

Noninvasive assessment of Wedensky modulated signal-averaged electrocardiograms.

The electrocardiographic (ECG) assessment of the T peak-T end (Tpe) intervals has been used in many clinical studies, but several related physiological aspects have not been reported. Specifically, the sources of the Tpe differences between different ECG leads have not been systematically researched, the relationship of Tpe duration to underlying heart rate has not been firmly established, and little is known about the mutual correspondence of Tpe intervals measured in different ECG leads. This study evaluated 796,620 10-s 12-lead ECGs obtained from long-term Holters recorded in 639 healthy subjects (311 female) aged 33.8 ± 9.4 years. For each ECG, transformation to orthogonal XYZ lead was used to measure Tpe in the orthogonal vector magnitude (used as a reference for lead-to-lead comparisons) and to construct a three-dimensional T wave loop. The loop roundness was expressed by a ratio between its circumference and length. These ratios were significantly related to the standard deviation of Tpe durations in different ECG leads. At the underlying heart rate of 60 beats per minute, Tpe intervals were shorter in female than in male individuals (82.5 ± 5.6 vs 90.0 ± 6.5 ms, p < 0.0001). When studying linear slopes between Tpe intervals measured in different leads and the underlying heart rate, we found only minimal heart rate dependency, which was not systematic across the ECG leads and/or across the population. For any ECG lead, positive Tpe/RR slope was found in some subjects (e.g., 79 and 25% of subjects for V2 and V4 measurements, respectively) and a negative Tpe/RR slope in other subjects (e.g., 40 and 65% for V6 and V5, respectively). The steepest positive and negative Tpe/RR slopes were found for measurements in lead V2 and V4, respectively. In all leads, the Tpe/RR slope values were close to zero, indicating, on average, Tpe changes well below 2 ms for RR interval changes of 100 ms. On average, longest Tpe intervals were measured in lead V2, the shortest in lead III. The study concludes that the Tpe intervals measured in different leads cannot be combined. Irrespective of the measured ECG lead, the Tpe interval is not systematically heart rate dependent, and no heart rate correction should be used in clinical Tpe investigations.

/pdf/heart-rate-dependency-and-inter-lead-variability-of-the-t-2rc627yfg2.pdf

Heart Rate Dependency and Inter-Lead Variability of the T Peak - T End Intervals.

The effects of procainamide and dofetilide (pure Class III antiarrhythmic agent) on the signal-averaged ECG (SAECG) were examined in relation to the results of programmed ventricular stimulation studies in 25 patients with inducible sustained monomorphic ventricular tachycardia. Procainamide prolonged significantly the total QRS and low amplitude signal durations (140 +/- 31 msec vs 166 +/- 48 msec, P 100 msec) in 15 of 27 drug trials. Of the procainamide induced SAECG changes, the fractional prolongation of the total QRS duration was the best parameter that identified effectively treated patients (24% +/- 16% in responders vs 10% +/- 11% in nonresponders, P 15% identified effectively treated patients with a sensitivity of 87%, specificity of 81%, and an overall predictive accuracy of 84%. Dofetilide did not change the SAECG, and no SAECG parameter predicted the results of programmed ventricular stimulation. The effects of both drugs on the spectral analysis (area ratios) and on the spectral temporal mapping (the values of normality factor) of the SAECG were not consistent. In conclusion, antiarrhythmic efficacy of procainamide can be predicted by the degree of drug induced prolongation of the signal-averaged QRS complex.(ABSTRACT TRUNCATED AT 250 WORDS)

Prediction of antiarrhythmic efficacy of class I and III agents in patients with ventricular tachycardia by signal-averaged ECG analysis.

E14-Compatible Holter Bin and QTcI
Introduction

The Holter bin method evaluates QT interval changes in the presence of heart rate changes without correcting the QT interval. However, the method does not allow time-matched comparisons, thus contradicting available guidance and good practice. We report a modification of the methods that allows time-matched comparisons without any heart rate correction.



Methods and Results

The modified Holter bin method (a) finds matching baseline heart rates for each QT reading on treatment and (b) calculates ΔQT values from the QT intervals on baseline and on treatment that match in heart rates. The difference between ΔQT values on active treatment and placebo provides the ΔΔQT value. The method was compared with the individual correction method in the data of the mirabegron thorough QT study in which supratherapeutic doses of this β3-adrenoceptor agonist led to substantial heart rate changes. The modified Holter bin method reproduced closely the results obtained with the individual heart rate correction. At all time points of the mirabegron study, the differences between the mean ΔΔQT values by the Holter bin method and the individual correction method were below 1 millisecond. Compared to the individual correction, the Holter bin method led to slight increases in the standard deviations of ΔΔQT values, but these were on average below 0.25 millisecond.



Conclusions

The Holter bin methodology can be modified to make it compatible with the available guidance and with good practice of clinical investigations. The results obtained with the modified Holter bin method are practically the same as with individualized heart rate corrected QT intervals. The close correspondence between the 2 methods demonstrates that the present possibilities of comparing QT interval duration in the presence of experiment-induced heart rate differences are not influenced by methodological artifacts.

ICH E14-compatible holter bin method and its equivalence to individual heart rate correction in the assessment of drug-induced QT changes.

Influence of the Noise and Artefact in Automatically Analysed Long Term Electrocardiograms on Different Methods for Time-Domain Measurement of Heart Rate Variability

Marek Malik

Papers

Noninvasive assessment of Wedensky modulated signal-averaged electrocardiograms.

Heart Rate Dependency and Inter-Lead Variability of the T Peak - T End Intervals.

Prediction of antiarrhythmic efficacy of class I and III agents in patients with ventricular tachycardia by signal-averaged ECG analysis.

ICH E14-compatible holter bin method and its equivalence to individual heart rate correction in the assessment of drug-induced QT changes.

Influence of the Noise and Artefact in Automatically Analysed Long Term Electrocardiograms on Different Methods for Time-Domain Measurement of Heart Rate Variability