Chronic sclerosing sialadenitis is a chronic (long-lasting) inflammatory condition affecting the salivary gland. Relatively rare in occurrence, this condition is benign, but presents as hard, indurated and enlarged masses that are clinically indistinguishable from salivary gland neoplasms or tumors. It is now regarded as a manifestation of IgG4-related disease.Involvement of the submandibular glands is also known as Küttners tumor, named after Hermann Küttner (1870–1932), a German Oral and Maxillofacial Surgeon, who reported four cases of submandibular gland lesions for the first time in 1896. Presentation
The inflammatory lesions in Küttners tumor may occur on one side (unilateral) or both sides (bilateral), predominantly involving the submandibular gland, but is also known to occur in other major and minor salivary glands, including the parotid gland. Overall, salivary gland tumors are relatively rare, with approximately 2.5–3 cases per 100,000 people per year seen in the Western world; however, salivary gland malignancies account for 3–5% of all head and neck cancers. However, salivary tumors show a great deal of morphological diversity, as well as variations in the nature of the lesion (malignant vs. benign):  approximately 20% to 25% of parotid tumors, 35% to 40% of submandibular tumors, and more than 90% of sublingual gland tumors are malignant. This situation underscores the diagnostic challenges in respect of Küttners tumor; despite being benign, this condition mimics the clinical appearance of malignancy in the salivary gland.
Tachycardia, also called tachyarrhythmia, is a heart rate that exceeds the normal resting rate. In general, a resting heart rate over 100 beats per minute is accepted as tachycardia in adults. Heart rates above the resting rate may be normal (such as with exercise) or abnormal (such as with electrical problems within the heart). Complications
Tachycardia can lead to fainting.When the rate of blood flow becomes too rapid, or fast  blood flow passes on damaged endothelium, it  increases the friction within vessels resulting in turbulence and other disturbances. According to the Virchows triad, this is one of the three conditions that can lead to thrombosis (i.e., blood clots within vessels). Causes
Some causes of tachycardia include:

Diagnosis
The upper threshold of a normal human resting heart rate is based on age. Cutoff values for tachycardia in different age groups are fairly well standardized; typical cutoffs are listed below:
1–2 days: Tachycardia >159 beats per minute (bpm)
3–6 days: Tachycardia >166 bpm
1–3 weeks: Tachycardia >182 bpm
1–2 months: Tachycardia >179 bpm
3–5 months: Tachycardia >186 bpm
6–11 months: Tachycardia >169 bpm
1–2 years: Tachycardia >151 bpm
3–4 years: Tachycardia >137 bpm
5–7 years: Tachycardia >133 bpm
8–11 years: Tachycardia >130 bpm
12–15 years: Tachycardia >119 bpm
>15 years – adult: Tachycardia >100 bpmHeart rate is considered in the context of the prevailing clinical picture. When the heart beats excessively or rapidly, the heart pumps less efficiently and provides less blood flow to the rest of the body, including the heart itself.