In the condition of ventricular tachycardia, the heartbeat is increased causing a sudden drop in the blood pressure, resulting in inability of the heart to pump blood to other body organs. Such sequence of events gives rises to the following symptoms:

• Development of discomfort in the chest followed by angina pain
• Fainting
• Dyspnea
• Palpitations
• Feeling of dizziness or light headedness
• In many cases, it may so happen that individuals may not experience any signs and symptoms [7].

• Congestive Heart Failure

  If a patient with a wide-complex tachycardia has a history of myocardial infarction, congestive heart failure, or recent angina pectoris, the tachycardia has a high likelihood of being ventricular in origin. [ncbi.nlm.nih.gov]

  You are more likely to experience VT if you live with a heart condition such as: Coronary heart disease – Plaque buildup in your coronary arteries leading to blockages Congestive heart failure – Fluid buildup in your body when your heart doesn’t pump [uncmedicalcenter.org]

  English Hypertension, supraventricular arrhythmias, congestive heart failure, chest pain and myocardial infarction have been associated with alfa interferon therapies, including Pegasys. [mymemory.translated.net]

  heart failure Get With The Guidelines®–Heart Failure Gold Quality Achievement Award from the American Heart Association/American College of Cardiology Top Performers on Key Quality Measures for heart attack and heart failure by The Joint Commission Cardiac [altabatessummit.org]

• Pallor

  On examination patient was conscious, oriented, had mild pallor but no icterus, cyanosis, edema or clubbing. She had a small non-tender lymph node palpable, in her left submandibular region. [casesjournal.biomedcentral.com]

  The monitor shows this: Ventricular Tachycardia, rate approximately 220 beats per minute During this rhythm she was awake, protecting her airway, with pallor, diaphoresis and cool extremities. Pulses were present. There was no respiratory distress. [hqmeded-ecg.blogspot.com]

  This includes blood pressure and appraisal of mental status, warmth of extremities, skin pallor, chest discomfort, diaphoresis, and nonspecific gastrointestinal symptoms. The patient may also be tachypneic from pulmonary edema and anxiety. [thecardiologyadvisor.com]

  […] examination findings of cannon A waves and variable intensity of the S1 heart sound suggest AV dissociation, a criterion favoring the diagnosis of ventricular tachycardia.[11] Patients may present with hypotension, altered mental status, diaphoresis, and pallor [ncbi.nlm.nih.gov]

• Tachycardia

  Ventricular Tachycardia Description Ventricular tachycardia (V-tach) is a rhythm with a rapid recurrence of premature ventricular contractions with no normal beats in between. [equimedcorp.com]

  Ventricular tachycardia may occur as a complication of a heart attack. [sharecare.com]

  tachycardia in patients with structural heart disease (1). [escardio.org]

  Due to the identification of polymorphic ventricular premature beats, nonsustained ventricular tachycardia (VT), and supraventricular tachycardia, a cardiogenic etiology was established. [ncbi.nlm.nih.gov]

• Palpitations

  Prior to the event, he experienced lightheadedness and palpitations. When he fainted, cardiopulmonary resuscitation was performed. Defibrillator pads were placed on the patient, which demonstrates pulseless ventricular tachycardia. [step2.medbullets.com]

  VT Symptoms If you experience a VT episode for more than a few seconds, you may have symptoms such as: Palpitations Dizziness Lightheadedness Shortness of breath Chest pain Loss of consciousness Signs of a potentially fatal VT episode may include difficulty [uncmedicalcenter.org]

  […] by using Valsalva maneuvers.[1] The rhythm of the palpitations may indicate the etiology of the palpitations (irregular palpitations indicate atrial fibrillation as a source of the palpitations).[1] An irregular pounding sensation in the neck can be [en.wikipedia.org]

  Types of Ventricular Tachycardia Monomorphic ventricular tachycardia Polymorphic ventricular tachycardia Torsades de pointe Symptoms Symptoms may include: Chest discomfort (angina) Fainting (syncope) Light-headedness or dizziness Palpitations Shortness [practicalclinicalskills.com]

  but don’t loose consciousness; Not tolerated ventricular tachycardia: the patient starts to complain palpitations, extreme weakness, and then quickly loses consciousness. [af-ablation.org]

• Heart Failure

  If a patient with a wide-complex tachycardia has a history of myocardial infarction, congestive heart failure, or recent angina pectoris, the tachycardia has a high likelihood of being ventricular in origin. [ncbi.nlm.nih.gov]

  You are more likely to experience VT if you live with a heart condition such as: Coronary heart disease – Plaque buildup in your coronary arteries leading to blockages Congestive heart failure – Fluid buildup in your body when your heart doesn’t pump [uncmedicalcenter.org]

  […] risk of mortality from heart failure.25 Patients require ongoing care and regular review after discharge. [aerjournal.com]

• Skipped Beats

  Since the new signal does not move through your heart muscle along the regular route, the heart muscle does not beat normally. Your heartbeat quickens, and you feel as if your heart is “skipping beats.” [texasheart.org]

  Symptoms include a rapid pulsation, an abnormally rapid or irregular beating of the heart.[1] Palpitations are a sensory symptom and are often described as a skipped beat, rapid fluttering in the chest, pounding sensation in the chest or neck, or a flip-flopping [en.wikipedia.org]

  When reported, symptoms generally consist of palpitations—often described as pounding in the chest, fluttering, or a sensation of skipped beats—and may also include light-headedness or chest discomfort. [onlinejacc.org]

• Irregular Heart Rhythm

  It arises in the heart’s lower chambers (ventricles) from tissues that generate a rapid and irregular heart rhythm. Ventricular tachycardia is a life-threatening emergency that may require an electrical shock therapy called cardioversion. [sharecare.com]

  If left untreated, some forms of ventricular tachycardia may get worse and lead to ventricular fibrillation (fast and irregular heart rhythm), which can be life-threatening. [wakemed.org]

• Dizziness

  VT Symptoms If you experience a VT episode for more than a few seconds, you may have symptoms such as: Palpitations Dizziness Lightheadedness Shortness of breath Chest pain Loss of consciousness Signs of a potentially fatal VT episode may include difficulty [uncmedicalcenter.org]

  Types of Ventricular Tachycardia Monomorphic ventricular tachycardia Polymorphic ventricular tachycardia Torsades de pointe Symptoms Symptoms may include: Chest discomfort (angina) Fainting (syncope) Light-headedness or dizziness Palpitations Shortness [practicalclinicalskills.com]

  If you experience unexplained fainting, dizziness, lightheadedness, shortness of breath or palpitations, you should be evaluated for possible ventricular tachycardia. [my.clevelandclinic.org]

  The symptoms of ventricular tachycardia may include: - Chest discomfort - Fainting - Lightheadedness or dizziness - Palpitations - Shortness of breath People experiencing ventricular tachycardia may also lose consciousness. [sharecare.com]

• Stroke

  This clinical case highlights the possible association of this pathology with recurrent ventricular tachycardia and stroke, and illustrates the importance of multimodal imaging approach in differential diagnosis. [ncbi.nlm.nih.gov]

  Gold Plus Quality Achievement Award and Target: Stroke Honor Roll Elite Plus Award from the American Heart Association/American Stroke Association Cardiovascular Imaging and Diagnostic Services Diagnosing Your Heart Problem The first step in dealing [altabatessummit.org]

  AF has two major complications— stroke and heart failure. In AF, blood can pool in the atria, causing blood clots to form. If a clot breaks off and travels to the brain, it can cause a stroke. [web.archive.org]

  A stroke can occur if a blood clot travels from the heart and blocks a smaller artery in the brain (a cerebral artery). For this reason, many patients with atrial fibrillation need antiplatelet therapy. [texasheart.org]

• Slurred Speech

  Case reports Case 1 An 87 year old man was admitted because of a sudden onset of shortness of breath and slurred speech. [bmj.com]

  speech/dysarthria, and CNS excitation (tremors, seizures) followed by CNS depression (decreased mental status and unconsciousness, respiratory depression). [errolozdalga.com]

• Vertigo

  […] their careers cut short by exercise-induced ventricular tachycardia. [5] Symptoms [ edit ] Symptoms experienced by patients with both sustained and non-sustained ventricular tachycardia may include: [2] [4] Palpitations Breathlessness Light-headedness Vertigo [en.wikibooks.org]

• Giddiness

  Vomiting persisted and two hours later she developed giddiness. She was referred to Sri Devaraj Urs Medical College Hospital, within three hours from the local hospital. On examination in the emergency room, she was in altered sensorium. [dx.doi.org]

• The preliminary diagnosis is done using electrocardiogram that measures the electrical activity of the heart. In case when the patient is hemodynamically stable then, 12-lead ECG and electrolyte levels are first obtained. ECG would also provide appropriate information regarding the cause, which leads to development of ventricular tachycardia. This would also help differentiate between potential arrhythmias [8]. 
• Following this, appropriate laboratory studies along with echocardiography and coronary angiography are indicated. These are required for designing a suitable treatment regime.
• Chest radiography is conducted in conditions, when presenting symptoms suggest heart failure or any other cardiopulmonary pathology as the causative factor. Imaging studies such as CT scan and MRI do not provide useful information for diagnosing ventricular tachycardia.

• Left Axis Deviation

  The QRS configuration in idiopathic left VT is shown in fig 14. They all have an RBBB shape because of an origin in the left ventricle. The most common type is shown in panel A. The frontal QRS axis shows left axis deviation. [heart.bmj.com]

  If the tachyarrhythmia has a left bundle branch block pattern but the electrical axis is more positive than 90° it suggests ventricular tachycardia. In general, left axis deviation suggests ventricular tachycardia. [ecgwaves.com]

  Axis shift of >40° between NSR and WCT- Right superior (northwest) axis (-90° to -180°)- Left axis deviation with RBBB morphology- Right axis deviation with LBBB morphology QRS Characteristics in precordial leads- QRS concordance either positive or [clinicaladvisor.com]

  Fascicular VT typically occurs in otherwise healthy young adults (between the ages of 15 and 40 years), presenting as an RBBB morphology tachycardia with left-axis deviation with a relatively narrow QRS duration (usually <140 ms) (60,61). [onlinejacc.org]

• Wide QRS Complex

  KEYWORDS: Algorithms; VT score; Ventricular tachycardia; Wide QRS complex tachycardia [ncbi.nlm.nih.gov]

  Electrocardiography (ECG) Diagnosis of ventricular tachycardia is by ECG (see figure Broad QRS ventricular tachycardia). Any wide QRS complex tachycardia (QRS ≥ 0.12 second) should be considered VT until proved otherwise. [merckmanuals.com]

  Distinguishing ventricular tachycardia from supraventricular tachycardias with wide QRS complexes Occasionally supraventricular tachycardias (which mostly have normal QRS complexes, i.e QRS duration <0.12 seconds) may display wide QRS complexes. [ecgwaves.com]

  Ventricular tachycardia as the default diagnosis in broad complex tachycardia. Lancet. 1994;343:386- 2) Brugada P, Brugada J, Mont L, et al. A new approach to the differential diagnosis of a regular tachycardia with a wide QRS complex. [ecglibrary.com]

• Prolonged QT Interval

  The patient's initial electrocardiogram was remarkable for a prolonged QT interval, and it was discovered that multiple family members had died of cardiac events as young adults. [ncbi.nlm.nih.gov]

  Triggered Activity – QRS falling on T-wave – occurs with prolonged QT interval - Electrolytes – Hypokalemia, Hypomagnesemia, Hypocalcemia - Drugs that prolong QT interval – many antiarrhythmics, Antibiotics, Antipsychotics, etc 5) Review Antiarrhythmic [errolozdalga.com]

  Patients with a prolonged QT interval have a higher risk for developing polymorphic VT. Removing offending drugs that prolong the QT interval and correcting potassium or calcium imbalances is crucial. [healio.com]

  Torsades de pointes (TdP) is a form of polymorphic VT occurring in the setting of a prolonged QT interval when a premature ventricular contraction follows a prolonged cardiac cycle. [clinicaladvisor.com]

• Right Bundle Branch Block

  Because the right bundle branch tends to have a slightly longer refractory period than the left bundle branch, at higher rates the right bundle branch may not be fully recovered from the previous cardiac cycle, which results in a right bundle branch block [aclsmedicaltraining.com]

  The alternation of the QRS is usually right bundle branch block with 180° swings in the frontal plane axis or, less commonly, alternation of right bundle branch and left bundle branch forms. [ncbi.nlm.nih.gov]

  The QRS complexes have a right bundle branch block pattern. Right ventricular outflow tract tachycardia Originates from the right ventricular outflow tract. The ECG typically shows right axis deviation, with a left bundle branch block pattern. [patient.info]

• Torsades De Pointes

  Torsades de pointes tachycardia See the separate article Torsades de Pointes. Polymorphic ventricular tachycardia Has the same ECG characteristics as torsades de pointes but in sinus rhythm the QT interval is normal. [patient.info]

  KEYWORDS: Dysrhythmia; Seizure; Torsades de pointes [ncbi.nlm.nih.gov]

  Types of Ventricular Tachycardia Monomorphic ventricular tachycardia Polymorphic ventricular tachycardia Torsades de pointe Symptoms Symptoms may include: Chest discomfort (angina) Fainting (syncope) Light-headedness or dizziness Palpitations Shortness [practicalclinicalskills.com]

• Atrioventricular Dissociation

  Atrioventricular dissociation (including fusion/capture beats and partial dissociation) was assigned two points. We recommend ≥3 VT score points for a firm diagnosis of VT. [ncbi.nlm.nih.gov]

  Atrioventricular dissociation usually is present. This means that the sinus node is depolarizing the atria in a normal manner at a rate either equal to, or slower than, the ventricular rate. [sjo.org]

  Note the presence of a premature and early narrow QRS complex (*) and atrioventricular dissociation (↓ ) indicative of ventricular origin. [revespcardiol.org]

  Do you see atrioventricular dissociation? If AV dissociation is present, the diagnosis is VT. AV dissociation occurs when P waves, representing atrial depolarization, are seen at different rates than the QRS complexes. [healio.com]

• T Wave Alternans

  In the pediatric population, although T-wave alternans do seem to be associated with serious VAs, other variables offer more information. [emedicine.com]

  Chow T, Kereiakes DJ, Bartone C, et al. Prognostic utility of microvolt T-wave alternans in risk stratification of patients with ischemic cardiomyopathy. J Am Coll Cardiol. 2006May2; 47 ( 9 ):1820-1827 Epub 2006 Apr 19 [ PubMed ] 34. [ncbi.nlm.nih.gov]

  Signal-averaged ECG, baroreflex sensitivity, heart rate variability, and T-wave alternans were not helpful for arrhythmia risk stratification. [academic.oup.com]

  Other noninvasive tests, such as T-wave alternans, signal-averaged ECG, and heart rate variability, do not provide diagnostic confirmation, but might be helpful in defining arrhythmia risk in patients with CAD. 17 Electrocardiographic Findings During [revespcardiol.org]

• Abnormal ECG

  However, a second and more precise evaluation of the abnormal ECG suggested a narrow supraventricular tachycardia, most probably AV nodal reentrant tachycardia with a 2:1 right bundle branch block. [ncbi.nlm.nih.gov]

  it still often leads to a number of electrocardiographic abnormalities. [en.wikipedia.org]

• The major goal of treatment of ventricular tachycardia is to manage any underlying disease condition. In emergency situations, patients are given cardiopulmonary resuscitation to stabilize the abnormal heart beats.
• Long term management of the condition includes administration of anti-arrhythmic medications. These however, have several side effects and should therefore be used with caution. In addition to medications, individuals are also given implantable cardioventer-defibrillator and catheter ablation [9]. Cardiac ablation is indicated in patients with recurrent ventricular tachycardia. This method is safer when compared to anti-arrhythmic medications and can also be safely used in patients with advanced heart diseases [10].
• Cardioverter–defibrillator is a type of device that is implanted under the skin, for constant monitoring and controlling heart’s rhythm. It is one of the most effective treatment regimens to avoid development of life threatening complications of ventricular tachycardia.
• In many cases, combination of treatment methods for managing the condition of patients with structural heart diseases is required.

Prognosis of ventricular tachycardia depends on the functioning of left ventricles. The underlying disease conditions and severity of the symptoms also affect the prognosis. However, left ventricular functioning may not always be the determining factor for prognosis of ventricular tachycardia. Studies have shown that individuals with good left ventricular functioning, but having long QT syndrome, and hypertrophic cardiomyopathy are at an increased risk of sudden death. It has been estimated that, about 30% individuals with non-sustained ventricular tachycardia and ischemic cardiomyopathy are more likely to suffer sudden death within 2 years of onset of disease. Prognosis is excellent in individuals with idiopathic ventricular tachycardia [6].

Heart diseases are the most common cause of ventricular tachycardia. Individuals with cardiomyopathy, myocarditis, heart failure, or valvular heart disease are at an increased risk of developing this condition. Ventricular tachycardia often is a common accompaniment in patients, who have undergone heart surgery.

In addition to underlying heart disorders the following factors can predispose an individual to develop ventricular tachycardia:

• Electrolyte imbalances, characterized by changes in the levels of potassium, magnesium and calcium
• Medications 
• Lack of oxygen
• Ph changes
• Development of systemic diseases such as systemic lupus erythematosus, rheumatoid arthritis, amyloidoisis, hemochromatosis and sarcoidosis
• Inherited channelopathies, which include long and short QT syndrome, catecholaminergic polymorphic ventricular tachycardia and Brugada syndrome [2]

The incidence rate of ventricular tachycardia is higher in the developed nations. In developing countries, the prevalence of these diseases is relatively low. It has been estimated that, in the US, ventricular tachycardia was the major cause of sudden death in about 300,000 cases each year [3].

Statistics have revealed that ventricular tachycardia accounts for 5.6% of all mortality. Men are more prone to develop the disease condition, mainly because of higher incidence of ischemic heart diseases in them. Females, who have long QT syndrome, are more prone to develop ventricular tachycardia [4].

Under normal physiological conditions, the heart rate is effectively controlled by the electrical signals, which are transmitted across the heart muscles. Various conditions may cause the signals to be sent too rapidly, leading to development of ventricular tachycardia. Rapid heartbeats in turn lead to decreased cardiac output which results from decreased ventricular filling. In conditions of ischemic heart disease and mitral valve insufficiency, there is also significant decrease in ventricular stroke output as well as reduced hemodynamic tolerance [5].

Majority of the cases of ventricular tachycardia cannot be prevented. However, individuals with underlying heart diseases should get it treated in order to prevent the onset of ventricular tachycardia.

Ventricular tachycardia (VT) is a dangerous form of arrhythmia, which can call for development of debilitating complications. Individuals affected by ventricular tachycardia, have heart rate of more than 100 beats/minute, accompanied by 3 or more irregular beats. Underlying disease condition, heart diseases, myocardial infarction and heart surgery, all can cause ventricular tachycardia to develop [1].

• Definition: Ventricular tachycardia is a condition, characterized by rapid heartbeats, which initiates from the ventricles. In this disorder, the pulse rate of the affected individuals goes beyond 100 beats/minute. 
• Cause: Patients with underlying disease conditions are at an increased risk of contracting ventricular tachycardia. Conditions such as cardiomyopathy, myocarditis, heart failure and valvular heart disease favor development of ventricular tachycardia. The condition can also occur as a complication in patients who have undergone heart surgery.
• Symptoms: Symptoms of tachycardia include discomfort in chest, light headedness, dizziness and palpitations. In many cases, individuals also experience shortness of breath and can even faint. 
• Diagnosis: Conducting electrocardiogram forms the basis of diagnosis procedure. This is done to measure the electrical activity of the heart. In addition to this, certain other tests such as chest radiography and coronary angiography would also be required.
• Treatment: In emergency situations, stabilizing the heart rate and bringing it to a normal state is the primary goal of treatment. Medications, catheter ablation and cardioverter defibrillation are also indicated depending on condition of the patient.

1. Turker Y, Ozaydin M, Acar G, Ozgul M, Hoscan Y, Varol E, et al. Predictors of ventricular arrhythmias in patients with mitral valve prolapse. Int J Cardiovasc Imaging. Feb 2010;26(2):139-45.
2. Brugada J, Brugada R, Brugada P. Channelopathies: a new category of diseases causing sudden death.Herz. May 2007;32(3):185-91
3. McNally B, Robb R, Mehta M, Vellano K, Valderrama AL, Yoon PW, et al. Out-of-hospital cardiac arrest surveillance --- Cardiac Arrest Registry to Enhance Survival (CARES), United States, October 1, 2005--December 31, 2010. MMWR Surveill Summ. Jul 29 2011;60(8):1-19
4. Buxton AE. Patients with nonsustained ventricular tachycardia. In: Sudden Cardiac Death: Prevalence, Mechanisms, and Approach to Diagnosis and Management, Akhtar M, Myerburg R, Ruskin J (Eds), Williams & Wilkins, Baltimore 1994.
5. Sarter BH, Finkle JK, Gerszten RE, Buxton AE. What is the risk of sudden cardiac death in patients presenting with hemodynamically stable sustained ventricular tachycardia after myocardial infarction? J Am Coll Cardiol 1996; 28:122.
6. Turakhia M, Tseng ZH. Sudden cardiac death: epidemiology, mechanisms, and therapy. Curr Probl Cardiol. Sep 2007;32(9):501-46.
7. Monserrat L, Elliott PM, Gimeno JR, et al. Non-sustained ventricular tachycardia in hypertrophic cardiomyopathy: an independent marker of sudden death risk in young patients. J Am Coll Cardiol 2003; 42:873.
8. Josephson ME, Callans DJ. Using the twelve-lead electrocardiogram to localize the site of origin of ventricular tachycardia. Heart Rhythm. Apr 2005;2(4):443-6.
9. Wellens HJ, Bär FW, Lie KI. The value of the electrocardiogram in the differential diagnosis of a tachycardia with a widened QRS complex. Am J Med. Jan 1978;64(1):27-33
10. Sarkozy A, Tokuda M, Tedrow UB, et al. Epicardial ablation of ventricular tachycardia in ischemic heart disease. Circ Arrhythm Electrophysiol 2013; 6:1115.